3000 AND 4000 ELECTRONIC CONTROLS TROUBLESHOOTING MANUAL
PREFACE
Welcome to the TS2973EN Troubleshooting Manual. We make every effort to keep our service
information current and accurate. Because of the time lag involved with writing and printing processes,
the transmission TCM may report a code that has not yet been added to this document. If you encounter
a code that is not yet in this publication, please call the Allison Transmission Technical Assistance Center
at 1-800-252-5283.
WTEC III ELECTRONIC CONTROLS TROUBLESHOOTING MANUAL
FOREWORD—How to Use This Manual
This manual provides troubleshooting information for the 3000 and 4000 Product Families Transmissions. Service
Manuals SM2148EN and SM2457EN, plus Parts Catalogs PC2150EN and PC2456EN may be used in conjunction
with this manual.
This manual includes:
•
Description of the WTEC III electronic control system.
•
Description of the electronic control system components.
•
Description of diagnostic codes, system responses to faults, and troubleshooting.
•
Wire, terminal, and connector repair information.
Specific instructions for using many of the available or required service tools and equipment are not included in
this manual. The service tool manufacturer will furnish instructions for using the tools or equipment.
Additional information may be published from time to time in Service Information Letters (SIL) and will be
included in future revisions of this and other manuals. Please use these SILs to obtain up-to-date information
concerning Allison Transmission products.
This publication is revised periodically to include improvements, new models, special tools, and procedures. A
revision is indicated by a new date on the title page and in the lower left corner of the rear cover. Contact your
Allison Transmission service outlet for the currently applicable publication. Additional copies of this publication
may be purchased from authorized Allison Transmission service outlets. Look in your telephone directory under
the heading of Transmissions—Truck, Tractor, etc.
Take time to review the Table of Contents and the manual. Reviewing the Table of Contents will aid you in quickly
locating information.
NOTE:Allison Transmission is providing for service of wiring harnesses and wiring harness components as
follows:
•
Repair parts for the internal wiring harness and for wiring harness components attached to the shift selector
will be available through the Allison Transmission Parts Distribution Center (PDC). Use the P/N from your
appropriate parts catalog or from Appendix E in this manual. Allison Transmission (AT) is responsible for
warranty on these parts.
•
Repair parts for the external harnesses and external harness components must be obtained from St. Clair
Technologies Inc. (SCTI). SCTI provides parts to any Allison customer or OEM and is responsible for
warranty on these parts. SCTI recognizes AT, manufacturers, and SCTI part numbers. SCTI provides a
technical HELPLINE at 519-627-1673 (Wallaceburg). SCTI will have parts catalogs available. The SCTI
addresses and phone numbers for parts outlets are:
St. Clair Technologies, Inc.
920 Old Glass Road
Wallaceburg, Ontario, N8A 4L8
Phone: 519-627-1673
Fax: 519-627-4227
St. Clair Technologies, Inc.
Calle Damanti S/N Col
Guadalupe—Guaymas
Sonora, Mexico CP85440
Phone: 011-526-2222-43834
Fax: 011-526 2222-43553
•
St. Clair Technologies, Inc. stocks a WTEC III external harness repair kit, P/N 29532362, as a source for
some external harness repair parts. SCTI is the source for external harness repair parts.
WTEC III ELECTRONIC CONTROLS TROUBLESHOOTING MANUAL
IMPORTANT SAFETY NOTICE
IT IS YOUR RESPONSIBILITY to be completely familiar with the warnings and cautions
used in this manual. These warnings and cautions advise against using specific service
procedures that can result in personal injury, equipment damage, or cause the equipment to
become unsafe. These warnings and cautions are not exhaustive. Allison Transmission could
not possibly know, evaluate, or advise the service trade of all conceivable procedures by which
service might be performed or of the possible hazardous consequences of each procedure.
Consequently, Allison Transmission has not undertaken any such broad evaluation.
Accordingly, ANYONE WHO USES A SERVICE PROCEDURE OR TOOL WHICH IS NOT
RECOMMENDED BY ALLISON TRANSMISSION MUST first be thoroughly satisfied
that neither personal safety nor equipment safety will be jeopardized by the service
procedures used.
Also, be sure to review and observe WARNINGS, CAUTIONS, and NOTES provided by the
vehicle manufacturer and/or body builder before servicing the Allison transmission in that
vehicle.
Proper service and repair is important to the safe and reliable operation of the equipment.
The service procedures recommended by Allison Transmission and described in this manual
are effective methods for performing troubleshooting operations. Some procedures require
using specially designed tools. Use special tools when and in the manner recommended.
The WARNINGS, CAUTIONS, and NOTES in this manual apply only to the Allison
transmission and not to other vehicle systems which may interact with the transmission. Be
sure to review and observe any vehicle system information provided by the vehicle
manufacturer and/or body builder at all times the Allison transmission is being serviced.
WARNINGS, CAUTIONS, AND NOTES
Three types of headings are used in this manual to attract your attention:
WARNING!
Is used when an operating procedure, practice, etc., which, if not correctly followed,
could result in injury or loss of life.
CAUTION:
NOTE:Is used when an operating procedure, practice, etc., is essential to highlight.
Is used when an operating procedure, practice, etc., which, if not strictly observed, could
result in damage to or destruction of equipment.
WTEC III ELECTRONIC CONTROLS TROUBLESHOOTING MANUAL
ECTION
S
1—GENERAL DESCRIPTION
1–1.TRANSMISSION
The World Transmission Electronic Controls (WTEC III) system features closed-loop clutch control to provide
superior shift quality over a wide range of operating conditions. The 3000 and 4000 Product Families transmissions
configurations can be programmed to have up to six forward ranges, neutral, and one reverse range. The MD 3070,
3700 SP, HD 4070/4076, 4700 RDS, 4700/4800 EVS, 4700/4800 SP have up to seven forward ranges and one
reverse.
Figure 1–1 is a block diagram of the basic system inputs and outputs.
SHIFT SELECTOR
RANGE AND
MODE SWITCH
SPEED SENSORS
THROTTLE POSITION SENSOR
RETARDER MODULAT ION
VEHICLE/ENGINE
COMMUNICATION LINKS
Figure 1–1. Electronic Control Unit Block Diagram
ECU
VIM
INPUTSOUTPUTS
DISPLAY
Figure 1–2 shows WTEC III electronic control components.
WTEC III Electronic Controls consist of the following elements:
•
Remote 12/24V Max Feature Sealed Electronic Control Unit (ECU)
Remote Pushbutton or Lever Shift Selector
•
•
Optional Secondary Shift Selector
OIL LEVEL SENSOR
SOLENOIDS
C3 PRESSURE SWITCH
TEMPERATURE SENSOR
(SUMP/RETARDER)
V03469
NOTE:
•
Throttle Position Sensor (TPS) (or electronic engine throttle data or PWM signal)
Engine, Turbine, and Output Speed Sensors
WTEC III ELECTRONIC CONTROLS TROUBLESHOOTING MANUAL
GENERAL DESCRIPTION
1–2.ELECTRONIC CONTROL UNIT (ECU)
The ECU (Figure 1–3) contains the microcomputer which is the brain of the control system. The ECU receives and
processes information defining:
Shift selector
•
•
Throttle position
•
Sump/retarder temperature
Engine speed
•
Turbine speed
•
•
Transmission output speed.
The ECU uses the information to:
•
Control transmission solenoids and valves
• Supply system status
• Provide diagnostic information.
Each ECU has a date code stamped on the label which is attached to the outer case of the ECU. This is the date
when the ECU passed final testing. This date is commonly used to denote the change configuration level of the
ECU. It is normal for the ECU date displayed electronically to be a few days prior to the date shown on the label.
keyedandcolor-codedto ensure thatthe properconnectorisattachedtothe correctECUsocket.
The colorof the connectorretainershould
match the color of the connector strain relief
BLUE
ECU
Figure 1–3. Electronic Control Unit (ECU)
(see AppendixE,Paragraph 1–1).
V07346.00.01
1–3.SHIFT SELECTOR
Pushbutton and lever shift selectors for the WTEC III Series are remote mounted from the ECU and connected to
the ECU by a wiring harness. All shift selectors except the strip-type pushbutton have a single digit LED display
and a mode indicator (LED). During normal transmission operation, illumination of the LED mode indicator shows
that a secondary or special operating condition has been selected by pressing the MODE button. During diagnostic
display mode, illumination of the LED indicator shows that the displayed diagnostic code is active. Display
brightness is regulated by the same vehicle potentiometer that controls dash light display brightness. More
information on both types of shift selectors is continued below.
A.Pushbutton Shift Selector (Figure 1–4)
There are three full-function pushbutton shift selectors and a strip pushbutton shift selector. Strip
pushbutton shift selectors are used by European OEMs. A full-function shift selector has a MODE
button and diagnostic display capability through the single digit LED display. The strip pushbutton
shift selector does not have a MODE button, diagnostic capability, or adjustable illumination. The
full-function pushbutton shift selector has six (6) pushbuttons which are R (Reverse), N (Neutral),
D (Drive),
by pressing the
has a raised lip to aid in finding it by touch. The MODE button is pressed to select a secondary or
special operating condition, such as ECONOMY shift schedule. Diagnostic and oil level (if sensor is
present) information is obtained by pressing the
↓(Down), ↑(Up), and MODE. Manual forward range downshifts and upshifts are made
↓(Down) or ↑(Up) arrow buttons after selecting D (Drive). The N (Neutral) button
WTEC III ELECTRONIC CONTROLS TROUBLESHOOTING MANUAL
GENERAL DESCRIPTION
The strip pushbutton shift selector has either three or six range selection positions as shown in Figure
1–4. When a strip pushbutton shift selector is used, diagnostic information must be obtained by using
the Allison DOC™ For PC–Service Tool, or a customer-furnished remote display.
DISPLAY
MODE ID
MODE
R
N
D
MODE INDICATOR
(LED)
MODE
BUTTON
CONTOURED VERSION
B. Lever Shift Selector (Figure 1–5)
The lever shift selector can have as many as six forward range positions (seven for the 7-speed
models), as well as R (Reverse) and N (Neutral). There is a hold override button which must be
pressed and held in order to move between certain selector positions. The hold override button must
be pressed when shifting between R, N, and D. The hold override button is released when the desired
selector position is reached. The selector lever can be moved freely between D and the numbered
forward ranges without pressing the hold override button. The lever selector can be chosen with the
lever on the left side or on the right side and with the R (Reverse) position toward the front or toward
the rear of the selector. Diagnostic and oil level (if sensor is present) information is obtained from the
LED display by pressing the DISPLAY MODE/DIAGNOSTIC button.
WTEC III ELECTRONIC CONTROLS TROUBLESHOOTING MANUAL
GENERAL DESCRIPTION
1–4.THROTTLE POSITION SENSOR (Figure 1–6)
The Throttle Position Sensor (TPS) can be mounted to the engine, chassis, or transmission. The TPS contains a pull
actuation cable and a potentiometer. One end of the cable is attached to the engine fuel lever and the other, inside a
protective housing, to the TPS potentiometer. Output voltage from the TPS is directed to the ECU through the
external harness. The voltage signal indicates the throttle position and, in combination with other input data,
determines shift timing.
A
Figure 1–6. Throttle Position Sensor (Without Mounting Brackets)
B
C
THROTTLE SENSOR
V00628
1–5.SPEED SENSORS (Figure 1–7)
The following three sensors provide information to the ECU:
• Engine speed−signal is generated by ribs on the torque converter pump.
• Turbine speed−signal is generated by the rotating-clutch housing spline contours.
• Output speed−signal is generated by a toothed member attached to the output shaft (except for the
3000 Product Family 7-speed models, where the toothed member is the transfer case idler gear).
The speed ratios between the various speed sensors allow the ECU to determine if the transmission is in the
selected range. Speed sensor information is also used to control the timing of clutch apply pressures, resulting in
the smoothest shifts possible. Hydraulic problems are detected by comparing the speed sensor information for the
current range to that range’s speed sensor information stored in the ECU memory.
WTEC III ELECTRONIC CONTROLS TROUBLESHOOTING MANUAL
GENERAL DESCRIPTION
MD/HD/B 300/B 400
ENGINE
(EXTERNAL)
HD/B 500
TURBINE
(EXTERNAL)
MD/B 300/B 400
TURBINE
(INTERNAL)
MD/B 300/B 400
(EXCEPT 7-SPEED)
RETARDER OUTPUT
(EXTERNAL)
MD 3070PT
OUTPUT
(INTERNAL)
MD/HD/B
OUTPUT
(EXTERNAL)
FORMER (BEFORE APPROXIMATELY JANUARY 1,2006
MD/HD/B
ENGINE
(EXTERNAL)
HD/B 500
TURBINE
(EXTERNAL)
MD/B 300/B 400
TURBINE
(INTERNAL)
MD/B 300/B 400
(EXCEPT 7-SPEED)
RETARDER OUTPUT
(EXTERNAL)
MD 3070PT 7-SPEED
OUTPUT
(INTERNAL HD)
MD/HD/B
OUTPUT
(EXTERNAL)
RETARDER
CURRENT (AFTER APPROXIMATELY JANUARY 1,2006)
SENSORS
Figure 1–7. Speed Sensors
V09818.00.00
1–6.CONTROL MODULE (Figure 1–8)
Pulse width modulated solenoids are used in the valve bodies. For valve locations, refer to SIL 27-WT-93.
The WTEC III Series transmission control module contains a channel plate on which is mounted a:
• Main valve body assembly.
• Stationary-clutch valve body assembly.
• Rotating-clutch valve body assembly.
The main valve body assembly contains:
• G solenoid and the C1 and C2 latch valves controlled by the solenoid.
• Main and lube regulator valves.
• Control main and converter regulator valves.
• Converter flow valve and exhaust backfill valves.
The stationary-clutch valve body assembly contains:
• C solenoid (C3)
• D solenoid (C4)
• E solenoid (C5)
• Solenoid regulator valves controlled by the solenoids
WTEC III ELECTRONIC CONTROLS TROUBLESHOOTING MANUAL
GENERAL DESCRIPTION
The rotating-clutch valve body assembly contains:
• A solenoid (C1)
• B solenoid (C2)
• F solenoid (lockup)
• Solenoid regulator valves controlled by the solenoids
• C3 pressure switch
The low valve body assembly (3000 and 4000 Product Families 7-speed) contains N and J solenoids.
3000 PRODUCT FAMILY CONTROL MODULE
(EXCEPT 7-SPEED MODELS)
3000 PRODUCT FAMILY 7-SPEED4000 PRODUCT FAMILY CONTROL MODULE
V07349.00.00
Figure 1–8. WTEC III Control Modules
A temperature sensor (thermistor) is located in the internal wiring harness. Changes in sump fluid temperature are
indicated by changes in sensor resistance which changes the signal sent to the ECU. Refer to Figure 6–8 in
Section 6, Code 24.
The oil level sensor (OLS) is a float type device mounted on the control module channel plate. The OLS senses
transmission fluid level by electronically measuring the buoyancy forces on the float. The sensor operates on
5 VDC supplied by the ECU. The oil level sensor is standard on 3000 and 4000 Product Families transmissions.
An OLS is required on all models with a shallow sump but is optional on other models. The oil level sensor is not
available on the 3000 Product Family 7-speed models.
The C3 pressure switch is mounted on the rotating-clutch valve body assembly and indicates when pressure exists
in the C3 clutch-apply passage. An accumulator/relay valve is in-line ahead of the C3 pressure switch and prevents
high frequency hydraulic pulses generated by the C3 solenoid from cycling the C3 pressure switch.
Also mounted on the control module is the turbine speed sensor for the 3000 Product Family transmissions. The
turbine speed sensor is directed at the rotating-clutch housing. The turbine speed sensor on the 4000 Product
Family transmissions is located on the outside of the main housing.
WTEC III ELECTRONIC CONTROLS TROUBLESHOOTING MANUAL
GENERAL DESCRIPTION
1–7.WIRING HARNESSES
A.External Wiring Harness (Figure 1–9)
The ECU uses three connectors labeled Black, Blue, and Gray, which are used to receive input from
the following:
TransmissionTPSDiagnostic tool connector
EngineVehicle interface module (VIM)Retarder
TurbineRetarder control moduleRetarder temperature sensor
Output speed sensorShift selectorAccumulator
Many harnesses will include a bulkhead fitting to separate cab and chassis components. Also, many
different styles and materials for harnesses are likely to be encountered.
NOTE:Allison Transmission is providing for service of wiring harnesses and wiring harness components as
follows:
• Repair parts for the internal wiring harness and for wiring harness components attached to the
shift selector will be available through the Allison Transmission Parts Distribution Center (PDC).
Use the P/N from your appropriate parts catalog or from Appendix E in this manual. Allison
Transmission is responsible for warranty on these parts.
• Repair parts for the external harnesses and external harness components must be obtained from St.
Clair Technologies Inc. (SCTI). SCTI provides parts to any Allison customer or OEM and is
responsible for warranty on these parts. SCTI recognizes Allison Transmission, manufacturers,
and SCTI part numbers. SCTI provides a technical HELPLINE at 519-627-1673 (Wallaceburg).
SCTI will have parts catalogs available. The SCTI addresses and phone numbers for parts outlets
are:
St. Clair Technologies, Inc.
920 Old Glass Road
Wallaceburg, Ontario, Canada N8A 4L8
Phone: 519-627-1673
Fax: 519-627-4227
• St. Clair Technologies, Inc. stocks a WTEC III external harness repair kit, P/N 29532362, as a
source for some external harness repair parts. SCTI is the source for external harness repair parts.
St. Clair Technologies, Inc.
Calle Damanti S/N Col
Guadalupe—Guaymas
Sonora, Mexico CP85440
Phone: 011-526 2222-43834
Fax: 011-526-2222-43553
WTEC III ELECTRONIC CONTROLS TROUBLESHOOTING MANUAL
GENERAL DESCRIPTION
B. Internal Wiring Harness (Figure 1–10)
The internal wiring harness provides connection between the external harness, the pulse width
modulated solenoids, oil level sensor, C3 pressure switch, and the temperature sensor.
TURBINE SPEED SENSOR
3000 PRODUCT FAMILY
(Omitted in 4000 Product Family)
OIL LEVEL SENSOR
3000 PRODUCT FAMILY
(Starting with S/N 6510220479)
OIL LEVEL SENSOR
3000 PRODUCT FAMILY
(Before S/N 6510220479)
LO SIGNAL SOLENOID (N)
3000 AND 4000 PRODUCT
FAMILIES 7-SPEED
C4 SOLENOID (D)
C6 SOLENOID (J)
3000 AND 4000 PRODUCT
FAMILIES 7-SPEED
C3 PRESSURE
C2 SOLENOID (B)
LU SOLENOID (F)
C1 SOLENOID (A)
SWITCH
FORWARD
SOLENOID (G)
C5 SOLENOID (E)
C3 SOLENOID (C)
Figure 1–10. WTEC III Internal Wiring Harness
1–8.VEHICLE INTERFACE MODULE(Figure 1–11)
OIL LEVEL SENSOR
4000 PRODUCT FAMILY
(Before S/N 6610048466)
FEEDTHROUGH HARNESS
STANDOFF
(3000 and 4000
Product Families
are different heights)
TEMPERATURE SENSOR –
TRANSID 1
TEMPERATURE SENSOR –
TRANSID 2
OIL LEVEL SENSOR
4000 PRODUCT FAMILY
(Starting with S/N 6610048466)
V07381.02.00
The vehicle interface module (VIM) provides relays, fuses, and connection points for interface with
the output side of the vehicle electrical system. VIMs are available for both 12V and 24V electrical
systems. The VIM for 12V systems uses all 12V relays. The VIM for 24V systems has all 24V relays.
Refer to the Parts Catalog for the transmission assembly number that you are servicing for detailed
parts information. Refer to Pages D–30 and D–31 for VIM wire number and terminal information.
Some OEMs may provide their own equivalent for the VIM which performs the same functions as the
VIM shown in Figure 1–11.
WTEC III ELECTRONIC CONTROLS TROUBLESHOOTING MANUAL
GENERAL DESCRIPTION
1–9.AUTODETECT FEATURE (V8, V8A, V9 SOFTWARE)
Autodetect is active on the first 24 engine starts or a larger calibration number of engine starts, depending upon the
component or sensor being detected (details follow in A through D below). Autodetect takes place within the first
30 seconds of each engine start monitored. Autodetect searches for the presence of the following transmission
components or data inputs:
RetarderPresent, Not Present
Oil level sensor (OLS)Present, Not Present
ThrottleAnalog, J1939, J1587
Engine coolant temperatureAnalog, J1939, J1587
Even after auotdetect has been completed, it can be reset to monitor an additional group of engine starts. Reset may
be necessary if a device known to be present is not detected or if an autodetectable component or sensor was added
after the initial vehicle build. Reset is accomplished by using Allison DOC™
AUTODETECT INFORMATION.” Allison DOC™
and manually enter the component or sensor to be recognized by the ECU by changing appropriate “customer
modifiable constants”.
For PC–Service Tool can also be used to override autodetect
For PC–Service Tool. Select “RESET
The four items above are the only customer modifiable constants (CMCs) that are autodetected. Other CMCs can
be changed at any time and are not related to autodetect. Consult Allison publication GN3433EN, User Guide, for
detailed instructions related to WTEC III “customer modified constants.” Additional details for each of the four
autodetectable features are given below.
A.Retarder
Autodetect searches for the presence of the H (retarder) solenoid during the first 24 engine ignition
cycles. The H solenoid must be present on the 24th engine start or the retarder is not detected and
will not function on subsequent engine starts.
If the retarder is present but not detected by autodetect, the retarder will not function. Be
sure to test for proper retarder function immediately after the 24th engine start. If the
WARNING
B. Oil Level Sensor (OLS)
NOTE:If an OLS is known to be present, but has not been detected, a possible cause is that the transmission
fluid level is too low. Determine the fluid level before beginning OLS troubleshooting.
retarder is not functioning, test H solenoid for open, short-to-ground, or short-to-battery
condition. Use Allison DOC™ For PC–Service Tool to reset autodetect or to manually
select the presence of the retarder after the H solenoid circuit is repaired.
No oil level sensor diagnostics take place until the OLS is detected. Frequently test for the presence of
oil level diagnostics if the transmission is known to contain an OLS. If an OLS is not detected during
the first 24 engine starts, autodetect continues for a larger calibration number of engine starts.
Autodetect stops when an OLS is detected or when the calibration number of starts is reached. When
the larger calibration number of engine starts is reached, the ECU concludes that no OLS is present. If
an OLS is known to be present, but has not been detected, troubleshooting the OLS circuit is required.
After the OLS circuit is repaired, reset autodetect or manually select the OLS function using Allison
DOC™ For PC–Service Tool.
WTEC III ELECTRONIC CONTROLS TROUBLESHOOTING MANUAL
GENERAL DESCRIPTION
C. Throttle Source (V8, V8A Software—See Paragraph 1–10C For V9A)
Whenever autodetect is functioning and no throttle source is found, a code 26 00 is logged. If a
datalink throttle source (J 1939 and J 1587) is detected, autodetect stops looking for that function.
However, if no analog throttle source was detected prior to engine start 25, autodetect continues for
engine starts 25 through a calibration number. Autodetect for analog throttle stops as soon as a device
is detected or when the calibration number of starts is reached. If an analog throttle source is known
to be present, but is not detected, troubleshooting of the analog throttle circuit is required. After the
analog throttle circuit is repaired, reset autodetect or manually select the analog throttle function
using Allison DOC™ For PC–Service Tool. An engine throttle source must be present.
A pulse width modulated (PWM) throttle source requires an unique calibration or must be manually
selected using Allison DOC™ For PC–Service Tool.
D. Engine Coolant Temperature Sensor Source
Autodetect looks for an engine coolant temperature source during the first 24 engine starts. However,
code 26 11 is not logged unless the calibration calls for engine coolant temperature data to be used for
retarder capacity reduction or preselected downshifts due to retarder overheating. Autodetect
remembers whatever engine coolant temperature source was present on engine start 24. If no analog
engine coolant temperature source is found on engine start 24, autodetect concludes that no sensor is
present. Therefore, if an engine coolant temperature source is known to be present at engine start 24,
but is not detected, troubleshooting of the engine coolant temperature circuit is required. After the
engine coolant temperature circuit is repaired, reset autodetect or manually select the engine coolant
temperature function using Allison DOC™ For PC–Service Tool.
1–10. AUTODETECT FEATURE (V9A, V9B, AND V9C SOFTWARE)
A.Retarder
Retarder autodetect software version V9A will countdown for a maximum of 25 ignition cycles while
recording detections of a retarder.
Retarder autodetect software version V9B and V9C will countdown for a maximum of 35 ignition
cycles while recording detections of a retarder.
A retarder will be identified as present and the retarder autodetect logic will stop once it is detected
for three consecutive ignition cycles. If the ignition cycle counter completes the 25 cycles (V9A) or
35 cycles (V9B, V9C) before there are three consecutive detections of a retarder, the software will log
that there is not retarder present and the retarder autodetect logic will stop.
B. Oil Level Sensor (OLS)
OLS autodetect will countdown for a maximum of 25 engine starts while recording detections of an
OLS. An OLS will be identified as present and the OLS autodetect logic will stop once it is detected
for:
• Five consecutive engine starts for software version V9A
• Three consecutive starts for software version V9B
• One engine start for software version V9C.
If the engine start counter completes 25 cycles before an OLS is detected (depending on the software
version specifications above), the software will log that there is not OLS present and the OLS
autodetect logic will stop. OLS detection must occur within 12.5 seconds on any given engine start.
WTEC III ELECTRONIC CONTROLS TROUBLESHOOTING MANUAL
GENERAL DESCRIPTION
Software version V9C will autodetect before an engine start if accumulated counts are greater than
100 or after an engine start if accumulated counts are greater than 25 but less than 100. No autodetect
occurs if accumulated counts are less than 25.
C. Throttle Source (Also Applies to V9 Software)
Throttle autodetect will increment a counter for a throttle source on each engine start during which
the possible throttle source is detected. When the counter for any of the sources indicates five
consecutive detections, the software will set a “confidence flag” to indicate that this is an available
throttle source. Multiple throttle sources can be detected on a single engine start and multiple
confidence flags can be set. There is no limit to the number of engine starts for autodetection of the
throttle source until a confidence flag is set for a source. Once a confidence flag is set for any one of
the sources, a counter begins to countdown for 15 additional engine starts. During the entire
autodetect period, the software will use the highest priority source as the throttle source if multiple
sources are detected before any confidence flags are set. Once a confidence flag is set, that source is
used as the source for the throttle signal. When the countdown period is complete, the software will
use the highest priority throttle source having a confidence flag set and the autodetect logic will stop.
D. Engine Coolant Temperature
Engine coolant temperature sensor autodetect will countdown for a total of 25 engine starts while
recording detections of engine coolant temperature sources. A “confidence flag” will be set once a
source is detected for five consecutive engine starts. Multiple sources detected before a confidence
flag is set or multiple confidence flags will result in the highest priority source being used as the
engine coolant temperature source. Multiple sources can be detected on a single engine start cycle.
1–11. TRANSID FEATURE
A.General Description
The TransID feature has been provided so that Allison Transmission can make component changes
which require calibration changes but still retain both the original transmission assembly number
(A/N) before feature based ordering (FBO) and the original calibrated ECU A/N. The purpose of
TransID is to reduce the need for OEMs to use cross-reference lists of transmission and calibrated
ECU A/Ns when such changes to the transmission are made. Since FBO began in April, 1998, the
OEM now needs to be sure the ECU being used is compatible with the TransID level stamped on the
nameplate of the transmission.
The basis for the TransID system is the creation of a TransID wire in the WTEC III system to provide
the signal to the ECU of the TransID level of the transmission. This wire will at first be connected
directly to the Analog Return (wire 135) to signal TransID level 1 (TID 1). TransID levels 2 through 8
will then be indicated by connecting the TransID wire in sequence to the return of solenoids A, B, C,
D, E, G, and F. Corresponding to the hardware changes is the ability in the V8A and later WTEC III
ECU to contain up to eight calibrations. The connection point of the TransID wire will provide the
signal to tell the ECU which calibration is required by the transmission.
Whenever a TransID level change is to be made, the new TransID level calibrations will be placed in
the PROM Calibration Configurator System (PCCS) before the change(s) is (are) made in production
to the transmissions. All ECUs programmed and sold after that date will then be loaded with the new
TransID level calibration. These ECUs will contain calibrations for the new level transmission and all
previous TransID levels and will automatically load the correct calibration for the transmission based
on the TransID signal sensed by AutoDetect during the first 25 engine starts. This eliminates worry on
the part of the OEM of coordinating the implementation of the new ECU and the new transmission
and allows their focus to be on using the stock of the earlier level ECU.
WTEC III ELECTRONIC CONTROLS TROUBLESHOOTING MANUAL
GENERAL DESCRIPTION
B. Transmission Changes Versus TransID Number
1. TransID 1
The internal wiring harness wiring change to make a TransID 1 (TID 1) transmission was put into
production before the introduction of the WTEC III system. The TID 1 internal harness was made
by connecting the C3 pressure switch ground (digital/signal ground; WTEC II wire 161) to the
sump temperature sensor and OLS ground (analog ground; wire 135) in the internal harness. In
WTEC II, the signal ground wire (wire 161) is routed through the transmission connector, terminal
W, and then to the ECU, terminal B27. In WTEC III, this same wire in the internal harness
becomes the TID wire (wire 195), and it goes to the ECU, terminal T13 (blue connector). The
purpose of TID 1 was to provide a common transmission for use with both WTEC II and
WTEC III systems (V7A and V8).
The only difference between a pre-TID transmission and a TID 1 transmission is the internal
wiring harness which connects the digital and analog grounds on the TID 1 harness. Adapter
harness P/N 200100 can be ordered from St. Clair Technologies to provide the same connection
outside the transmission and allow a pre-TransID transmission to be “converted” to a TransID 1
transmission.
All models of the 3000 and 4000 Product Families transmissions were built with the TID 1 internal
(feedthrough) harness beginning in September, 1996. Two changes were rolled into this update: the
wiring change for TID 1 and a change to use a molded channel rather than the braided covering
which was previously used. Both changes were rolled into the same internal harness P/N even
though there was a delay in implementing the channel which resulted in the two serial number (S/N)
breaks. Table 1–1 lists the harness P/Ns for the different transmission models along with the S/Ns
for both changes for each harness.
Table 1–1. TransID 1 S/N Breakpoint
Pre-TransID
Transmission Model
3000 Product Family w/ OLS295163222952947265100888646510096671
3000 Product Family w/o OLS295163232952947365100893166510096683
3000 Product Family 7-Speed295163242952947465100907866510096675
4000 Product Family w/ OLS295163252952947566100140676610015591
4000 Product Family w/o OLS295163262952947666100140846610015700
4000 Product Family 7-SpeedN/AN/AN/AN/A
*NOTE: These P/Ns are no longer serviced, refer to Table 1–4 for current P/Ns.
2. TransID 2
The purpose of the TransID 2 (TID 2) change is to indicate the use of new sump and retarder
temperature sensors (thermistors) and a new 3000 Product Family retarder design. The new
retarder requires a different calibration than the old retarder. Retarder performance complaints will
occur if the new retarder is controlled by the old retarder calibration or the old retarder is
controlled by the new retarder calibration.
TID 2 internal harnesses contain both the new sump temperature sensor and a new connection
point for the TID wire. The TID wire (195) is connected to Solenoid A ground (wire 120) to signal
TID 2 to the ECU. The new temperature sensors are discussed below.
A TID 2 transmission will only work with a V8A or later ECU (WTEC III) and V8A and later
ECUs are calibrated to accommodate both TID 1 and TID 2 transmissions. The 4000 Product
Family 7-Speed transmissions were equipped with TID 2 at the start of production. The 3000 and
4000 Product Families transmissions produced before April 3, 2000 were TID 2 units.
WTEC III ELECTRONIC CONTROLS TROUBLESHOOTING MANUAL
GENERAL DESCRIPTION
The internal harness change to all models for TID 2 production began in late December, 1997.
The S/N breakpoints are shown in Table 1–2.
Table 1–2. TransID 2 S/N Breakpoint
Transmission Model
TransID 1
Harness P/N*
TransID 2
Harness P/N*
S/N at Thermistor and
Wiring Change
3000 Product Family w/ OLS29529472295336526510141464
3000 Product Family w/o OLS29529473295336536510141470
3000 Product Family 7-Speed29529474295336546510142172
4000 Product Family w/ OLS29529475295336556610026328
4000 Product Family w/o OLS29529476295336566610026319
4000 Product Family 7-SpeedN/A29533657
*NOTE: These P/Ns are no longer serviced, refer to Table 1–4 for current P/Ns.
6610034908
(start of production)
The new retarder thermistor used on TID 2 retarder model transmissions has a molded connector
and is the same on all TID 2 retarders. The TID 1 and pre-TID retarder thermistor had a two
terminal connector attached to it when it was used on 4000 Product Family transmissions. It was
part of a retarder harness assembly when used on 3000 Product Family transmissions. Refer to
Appendix Q which describes the new and old temperature sensors. A graph and a table of
resistance values for different temperatures are also included in Appendix Q.
Table 1–3 shows the old (pre-TID and TID 1) and the new (TID 2) part numbers of the retarder
temperature sensors and the serial number when the change was made.
Table 1–3. New Retarder Temperature Sensor S/N Breakpoint
Transmission ModelFormer Thermistor Used
P/N Where
Former
Thermistor Used
New
Thermistor
P/N (TID 2)
First S/N
For New
Thermistor
3000 Product Familybuilt into retarder harness29510662153263096510142059
4000 Product Familybuilt with connector attached29511861153263096610026472
3. TransID 3
Starting April 3, 2000, the TID feature was changed from TID 2 to TID 3. A new internal harness
was released to implement the TID 3 feature. Figure J–3 (Appendix J) shows the wiring schematic
for the new internal harness. TID 1 and TID 2 internal harnesses have been maintained for service
units built before April 3, 2000. TID 3 is required to make sure that the auto-detect feature selects
the proper calibration for the new friction plate material.
Version 8A software was updated to include TID 3 capability as of October 1999. Table 1–4 shows
the new internal harness part numbers for each of the control module configurations. Also
reference Table 1–5 for transmission/ECU compatibility information. The 3000 and 4000 Product
Families transmissions produced starting April 3, 2000 were TID 3 units. All T Series
transmissions were TID 3 at introduction.
WTEC III ELECTRONIC CONTROLS TROUBLESHOOTING MANUAL
GENERAL DESCRIPTION
†
Table 1–4. Current Internal Harness Service Kit
3000 and 4000 Product Families Internal Harness Service Kits
Transmission
TransID 1TransID 2 **TransID 3***
3000 Product Family w/o OLS295426832954268029542660
3000 Product Family w/ OLS (old)*2954268229542677N/A
3000 Product Family w/ OLS (new)*295426512954267129542681
3000 Product Family 7-Speed295426842954267929542687
4000 Product Family w/o OLS295426862954264929542688
4000 Product Family w/ OLS (old)*2954268529542648N/A
4000 Product Family w/ OLS (new)*295441412954267029542689
4000 Product Family 7-Speed w/o OLSN/A2954265029542690
4000 Product Family 7-Speed w/ OLSN/AN/A29542691
*Reference SIL 19-WT-99
**Reference SIL 7-WT-98
*** Reference SIL 4-WT-00N/A Not Applicable
† The key words associated with this reference are “current” and “kits”.
C. Compatibility Between TransID Level And ECU Calibration Level
Table 1–5 shows the compatibility of the different ECU software levels with the different TID level
transmissions.
Table 1–5. ECU/TransID Compatibility
P/N by TransID Version
WTEC II
WTEC III
CIN Compatibility
Number
Software
Level
Compatible with
TransID Level
ECU Production
Dates
07V6Epre-TID and TID 1until 9/94
08V7 and V7Apre-TID and TID 19/94 until 12/97
0AV8TID 12/97 until 9/97
0BV8ATID 1 and 2beginning 10/97
0CV9TID 1, 2, and 3beginning 4/00
0DV9ATID 1, 2, and 3beginning 4/01
The manufacture and sale of both WTEC II and WTEC III ECUs during most of 1997 required a
means of using a common transmission with either a WTEC II or a WTEC III ECU. A TID 1
transmission is the common transmission configuration for both control systems and production
began in September, 1996 (refer to Table 1–3). A TID level 1 transmission is compatible with any
Allison-supplied ECU.
Pre-TransID transmissions are only compatible with V6E, V7, and V7A ECUs. Pre-TransID
transmissions were produced before the first S/N break in Table 1–3.
TransID level 2 transmissions were produced beginning in late December, 1997 (refer to
Table 1–5). A TransID 2 transmission is compatible with V8A and later ECUs only.
TransID level 3 transmissions were produced beginning April 3, 2000 (refer to Table 1–5). A
TransID 3 transmission is compatible with V8A and later ECUs only. Software V9 or V9A is required
to use Reduced Engine Load at Stop (RELS). Refer to Table 1–6 for S/N break points.
WTEC III ELECTRONIC CONTROLS TROUBLESHOOTING MANUAL
GENERAL DESCRIPTION
The following table shows compatibility information between transmission and vehicle configuration.
Vehicle Configuration (ECU, Shifter, and Wiring)
Transmission
Configuration
Pre-TID 3000 and 4000
Product Families;
Raybestos plates only
TID1: 3000 and 4000
Product Families;
Raybestos plates only
TID2: 3000 and 4000
Product Families; New
style sump and retarder
temp sensors; 3000
Product Family new
style retarder; Raybestos
plates only
TID2: 3000 and 4000
Product Families; New
style sump and retarder
temp sensors; 3000
Product Family new
style retarder; Dynax
plates only
*V9x refers to the latest V9 version
WTEC II, C6E;
CIN 07
everything works OK; no
cal change required or
available if Luk damper/
friction material used;
replace vehicle harness
connector with 29519127
kit
everything works OK; no
cal change required or
available if Luk damper/
friction material used;
replace vehicle harness
connector with 29519127
kit
will not work; codes 44
12, 33 23, 24 23, 33 12;
retarder codes 61 00, 62
23, and 62 12; non-rtdr
models can work if
changed back to TID1
internal harness; 4000
Product Family rtdr
models require change
back to old style retarder
temp sensor; 3000 Product
Family rtdr models
require change back to old
style retarder; no cal
change required or
available if Luk damper/
friction material used; if
converted, replace vehicle
harness connector with
2951927 kit
will not work; code 44 12
and temp sensor codes;
requires WTEC III, V8A,
V9 through V9x* system
or overhaul to change
back to Raybestos clutch
plates
WTEC II, V7;
CIN 08
everything works OK; no
cal change required or
available if Luk damper/
friction material used, but
latest cal has changes to
better match the friction
material
everything works OK;
recal if Luk damper/
friction material used,
because latest cal has
changes to better match
the friction material
will not work; codes 44
12, 33 23, 24 23, 33 12;
retarder codes 61 00, 62
23, and 62 12; non-rtdr
models can work if
changed back to TID1
internal harness; 4000
Product Family rtdr
models require change
back to old style retarder
temp sensor; 3000 Product
Family rtdr models
require change back to old
style retarder; recal if Luk
damper/friction material
used, because latest cal
has changes to better
match the friction material
will not work; code 44 12
and temp sensor codes;
requires WTEC III, V8A,
V9 through V9x* system
or overhaul to change
back to Raybestos clutch
plates
WTEC III, V8;
CIN 0A; TID1
(accommodates both
lockup clutches after 8/
25/97)
will not work unless
TID1 level trans; codes
32 xx, 55 xx; use
adapter 200100 to make
it a TID1; recal if Luk
damper/friction material
used, because latest cal
has changes to better
match the friction
material
everything works OK;
recal if Luk damper/
friction material used,
because latest cal has
changes to better match
the friction material
will not work; will use
TID1 cal and generate
codes: 33 23, 24 23, 33
12; retarder codes 61 00,
62 23, and 62 12; recal
to V8A (CIN 0B)
will not work; generate
codes: 33 23, 24 23, 33
12; retarder codes 61 00,
62 23, and 62 12; Shift
quality problems
because of clutch
material change; recal
ECU to V8A, V9
through V9x*; if RELS
required, replace ECU
with V9
WTEC III, V8A;
0B; TID1 & 2
(+TID 3 after 10/24/99,
but will not handle
TELS)
will not work unless
TID1 level trans; codes
32 xx, 55 xx; use
adapter 200100 to make
it a TID1; works with
Luk or BW damper
everything works OK;
uses TID1 cal
everything works OK;
uses TID2 cal
will not work if cal
installed before 10/24/99;
will not work with
RELS; generate code 36
01 and have shift quality
problems because of
clutch material change;
recal ECU to latest V8A
if previous cal installed
before 10/24/99; if
RELS required, replace
ECU withV9 through
V9x*
CIN 0C through 0F;
(required for RELS)
will not work unless
TID1 level trans;
codes 32 xx, 55 xx;
use adapter 200100 to
make it a TID1; works
with Luk or BW
damper
WTEC III ELECTRONIC CONTROLS TROUBLESHOOTING MANUAL
SECTION 2—DEFINITIONS AND ABBREVIATIONS
2–1.CHECK TRANS LIGHT
When the ECU detects a serious fault, the CHECK TRANS light (usually located on the vehicle instrument panel)
illuminates and action is automatically taken to protect operator, vehicle, and the transmission. A diagnostic code will
nearly always be registered when the CHECK TRANS light is on; however, not all diagnostic codes will turn on the
CHECK TRANS light. Codes related to the CHECK TRANS light are detailed in the code chart (refer to Section 6).
Illumination of the CHECK TRANS light indicates that a condition was detected that requires service attention.
Operation may or may not be restricted but even when restricted will allow the vehicle to reach a service assistance
location. Depending upon the cause for the CHECK TRANS light illumination, the ECU may or may not respond
to shift selector requests. The transmission may be locked in a range. That range will be shown on the shift selector
display. Both upshifts and downshifts may be restricted when the CHECK TRANS light is illuminated. Seek
service assistance as soon as possible.
Each time the engine is started, the CHECK TRANS light illuminates briefly and then goes off. This momentary
lighting shows the light circuit is working properly. If the light does not come on during engine start, request
service immediately.
2–2.ALLISON TRANSMISSION DIAGNOSTIC TOOL
Allison DOC
4000 Product Families transmissions. The Allison DOC
application supporting WTEC II and WTEC III control systems. When installed on the user’s own PC, it will allow
the technician to acquire data from the transmission’s control system and through the use of embedded
troubleshooting manuals, conduct systematic troubleshooting of transmission complaints.
(Diagnostic Optimized Connection) For PC is a PC-based service tool for use with 3000 and
for PC–Service Tool is a full-feature diagnostic software
Basic Features
Allison DOC For PC–Service Tool uses a Windows style GUI and includes:
• User selected views of multiple transmission parameters.
• View active and historical diagnostic trouble codes (DTCs).
• Graphical instrument panel view of transmission parameters.
• Strip chart function .
• User configurable Snapshot function.
• User configurable Print function.
• Code driven links to embedded WTEC II, WTEC III (Pre-4
4000 Product Families) Troubleshooting Manuals.
• Reprogramming capability (available after satisfying Allison Transmission training certification
requirements).
• Demo Mode which allows the user to practice the program without being connected to a vehicle.
• New animated, screen by screen, help support (found in Help, Video-based training materials, Allison
For PC–Service Tool Training Videos).
DOC
• Application Configuration: This menu function serves as the platform for three different features.
(1) General tab, which allows the user to select language (English only at this time), and unit of measure.
(2) ECU/TCM Reprogramming tab, used to enable the reprogramming capability of the Allison DOC
For PC–Service Tool.
(3) Update Application tab, will access a web URL that will contain minor updates for the diagnostic
tool to support changes in the various transmission control systems.
• Data Bus Viewer allows the user to capture (see and save) data transmitted on the various vehicle data
buses supported by Allison DOC
• Printed user’s manual and laminated Job Aid Card.
For PC–Service Tool (J1708, J1939, GMLAN, and J1850).