MoTeC LTCN User Manual

MoTeC LTC User Manual

Contents

Introduction .............................................................................. 2

Installation ................................................................................ 4

LTC Installation ..................................................................................... 4

Lambda Sensor Installation .................................................................. 4

LTC Manager Software Installation ...................................................... 6

Configuration ........................................................................... 8

Introduction ........................................................................................... 8

Setup..................................................................................................... 8

Calibration ........................................................................................... 13

Firmware ............................................................................................. 16

Operation ................................................................................ 17

Monitoring LTCs ................................................................................. 17

MoTeC Data Loggers ......................................................................... 20

MoTeC 'Hundred Series' ECUs .......................................................... 21

Lambda and Air Fuel Ratio ................................................................. 24

LTC Operating Tips ............................................................................ 26

Appendices ............................................................................ 27

Appendix A – Specifications ............................................................... 27

Appendix B – Pinout ........................................................................... 28

Appendix C – Dimensions .................................................................. 30

Appendix D – Wiring Details ............................................................... 33

Appendix E – LTC CAN Messages ..................................................... 36

Appendix F – Lambda to Air Fuel Ratio Table .................................... 39

Copyright  2011 – MoTeC Pty Ltd

The information in this document is subject to change without notice.

While every effort is taken to ensure correctness, no responsibility will be taken for the

consequences of any inaccuracies or omissions in this manual.

V1.5 15 September 2011

2 Introduction

Introduction

MoTeC LTCs (Lambda to CAN) monitor and control Wideband Lambda
sensors and transmit Lambda readings and diagnostics on a CAN bus. There
are single channel LTC and Dual channel LTCD available to suit either Bosch
LSU4.9 or NTK sensors:

• #61300 – Single channel Bosch LSU 4.9 Sensor

• #61301 – Dual Channel Bosch LSU 4.9 Sensors

• #61304 – Single Channel NTK Sensor

• #61305 – Dual Channel NTK Sensors

Up to 32 Lambda sensors can be configured on a single CAN bus using LTCs,
allowing an ECU or Data Logger to simultaneously monitor multiple Lambda
sensors.

Throughout this manual the LTC, LTCD, LTC-N and LTCD-N will be referred to
as LTC except where details specific to a particular model are discussed.

Features

• Accurate Lambda measurement even when the exhaust gas temperature
is changing rapidly (heating or cooling)

• Ability to perform free air sensor calibration or use the initial sensor factory
calibration. LTC-N has the ability to be calibrated against a test gas.

• Pre-configured to work in a single LTC or LTCD installation, without
requiring configuration with a PC

• LTC Manager software to:

o configure and calibrate all LTCs on the CAN bus
o display readings and diagnostics
o configure the CAN transmission address of each LTC
o control free air calibration
o update LTC firmware

Compatibility

• MoTeC ‘Hundred series’ ECUs: M400, M600, M800 and M880

• MoTeC M1 Series ECUs

• MoTeC Data Loggers : SDL, SDL3, ADL, ADL2, ADL3, ACL

MoTeC Introduction 3

Accessories

• #57006 Bosch LSU 4.9 Lambda Sensor

• #57007 NTK Lambda Sensor

• #61059 MoTeC UTC - USB to CAN, used to communicate to the PC

(optional)
Note: LTC is not compatible with MoTeC's CAN cable (part number

61021)

4 Installation

Installation

LTC Installation

The LTC can be mounted to a flat surface using the two mounting holes.

The LTC should be mounted as far as possible from the exhaust to avoid
excessive heat.

Note: LTC maximum ambient temperature is 100 °C.

Use Connector A to connect the single LTC to the Lambda sensor. Use
connectors A and B to connect the LTCD to two Lambda sensors. Use the
Power/CAN Connector to power the LTC and connect to the CAN bus.

See Appendices for more details.

Lambda Sensor Installation

Warning: The Bosch LSU 4.9 Lambda sensors are fitted from the factory with

a calibrated trimming resistor embedded in the sensor connector. If the factory
sensor connector is cut off and replaced with another type, the LTC will not
operate correctly.

Note: Unlike the Bosch LSU 4.9 the NTK sensors standard connector can be

removed and replaced by a non-standard connector without affecting the
performance of the sensor or the LTC-N. However, the initial factory calibration
method will not work as the calibration resistor is built into the original
connector. In this case Free Air calibration is required. It is recommended that
no wiring modification is made to the NTK sensor or LTC-N unless completely
necessary.

The Lambda sensor should be fitted to the exhaust system with the sensor tip
protruding into the exhaust gas flow. The following considerations should be
taken into account when fitting the sensor:

• Place the sensor on an angle between 10 and 90 degrees to the vertical
with the tip of the sensor pointing down to prevent condensation build up
between the sensor case and the sensor ceramic.

• Do not place the sensor in a vertical position; excess heat soak will prevent
proper operation.

• Place the sensor at least 1 meter from the exhaust ports to avoid
excessive heat (recommended).

MoTeC Installation 5

• Place the sensor at least 1 meter from the open end of the exhaust system
to avoid incorrect readings due to outside oxygen (recommended)

o Where necessary for shorter exhaust systems the sensor could be

placed closer to the engine.

• Place the sensor away from the flame front coming out of the cylinder head
and away from areas where one cylinder may have more effect than
another.

Correct sensor placement

• If possible, do not place the sensor near exhaust slip joints; some designs
allow air to enter resulting in incorrect readings.
If the sensor has to be placed near a slip joint, reverse the slip joints to
reduce the influence of introduced air.

Introduced air No air introduced

Exhaust flow

Exhaust slip joint design

Incorrect sensor
placement

6 Installation

LTC Manager Software Installation

The LTC Manager software is required for configuration and calibration of LTC
units. The software must be installed on Windows XP or Windows Vista. The
same software package is used for the LTC, LTCD, LTC-N and LTCD-N.

Note: The LTC Manager software is not required if using a single LTC or
LTCD unit preconfigured by MoTeC.

MoTeC Installation 7

Install LTC Manager Software

• Go to the MoTeC website at www.motec.com and navigate to downloads >
software > latest releases > LTC Manager

OR

Locate LTC Manager installation file on the MoTeC Resource Disc

• Save the LTC Manager installation file in your preferred location (for
example desktop)

• Double click the saved file to run the installer

• Follow the installation instructions on the Install Shield Wizard

• To start the program after installation,

double click the LTC Manager icon on the desktop

OR

Click Start > All Programs > MoTeC > LTC > LTC Manager

Updating Software

Software updates are available free of charge, giving access to the latest
features for the life of the device. Download the latest software versions from
the website and follow the software installation instructions to update to the
new version.

To update the associated firmware in the device see Firmware.

8 Configuration

Configuration

Introduction

Note: LTC units come pre-configured to suit a single LTC or LTCD unit
installation using the initial factory sensor calibration.

The default CAN address for the singular LTC is hex 460.
The default CAN addresses for LTCD is hex 460 for Lambda sensor 1 and hex
461 for Lambda sensor 2.

LTC Manager is used to individually configure and calibrate the connected LTC
units. Configuration using LTC Manager is only necessary if installing multiple
LTC units or if changes to the default settings are required.

All LTC configuration and calibration operations are performed directly on an
LTC and configurations are not stored on disk.

Start LTC Configuration

• Connect the unit to the PC (see Appendix D – Wiring Details)

• Ensure the unit is powered

• Start LTC Manager

o Click the LTC Manager icon on the desktop

OR

o Click Start > All Programs > MoTeC > LTC > LTC Manager.

The main LTC Manager window displays the live configuration and status of all
LTC units present on the connected CAN bus.

Setup

CAN Address

The CAN setup determines which CAN address (specified in hex) the LTC
uses to transmit readings and diagnostic information. The format of the CAN
messages is described in. Appendix E – LTC CAN Messages

Each LTC on a CAN bus must be configured with a unique CAN address.

See

Operation for information on configuring a MoTeC Data Logger or ECU to

receive LTC CAN messages.

MoTeC Configuration 9

LTC Unit Setup

• To open the LTC Setup window, double click the row in the table
containing the LTC or click the row and click Setup.

• Select the Recommended Address check box and enter one of the
addresses in the drop down box to communicate with MoTeC products
such as Data Loggers or 'hundred series' ECUs.
The recommended address range for LTC messages is hex 460 to hex
47F.

OR

Select the Custom Address check box and enter an address (in hex) for
interfacing with third party equipment.

OR

Select Disabled to prevent an LTC from transmitting CAN messages.
While disabled an LTC will not heat the sensor or perform Lambda
measurements.

Note: Lambda sensors should not be left in the exhaust system of a
running engine if they are not being controlled. A disabled sensor in a
running engine can be damaged.

• In the Name area the default name will appear. The default name matches
the selected CAN Address (LTC1 etc.). If required the user can specify a
custom name (e.g. Left Bank or Cylinder 4).

Tip: The rows in the main LTC Manager window are sorted by the Name
column.

10 Configuration

• Click OK. The configuration updates will be sent to the LTC, this may take

several seconds

LTC-N Unit Setup

• To open the LTC Setup window, double click the row in the table
containing the LTC or click the row and click Setup.

• Select the Recommended Address check box and enter one of the
addresses in the drop down box to communicate with MoTeC products
such as Data Loggers or 'hundred series' ECUs.
The recommended address range for LTC messages is hex 460 to hex
47F.

OR

Select the Custom Address check box and enter an address (in hex) for
interfacing with third party equipment.

OR

Select Disabled to prevent an LTC from transmitting CAN messages.
While disabled an LTC will not heat the sensor or perform Lambda
measurements.

MoTeC Configuration 11

Note: Lambda sensors should not be left in the exhaust system of a
running engine if they are not being controlled. A disabled sensor in a
running engine can be damaged.

• In the Name area the default name will appear. The default name matches
the selected CAN Address (LTC1 etc.). If required the user can specify a
custom name (e.g. Left Bank or Cylinder 4).

Tip: The rows in the main LTC Manager window are sorted by the Name
column.

• Select a Standard Sensor type from the drop down menu

OR

Select a Custom Sensor

Note: Custom sensor setups are for advanced users and it is not
recommended for general use.

• Select a Standard Output Table, generally Lambda to three decimal
places

OR

Use a Custom Table for another type of fuel, e.g. Diesel.

• Click OK. The configuration updates will be sent to the LTC, this may take

several seconds

LTC-N Output Table

The standard output table for the LTC-N is for Lambda to three decimal places.
It is possible for the user to make a custom table to suit the Air/Fuel ratio of any
fuel.

12 Configuration

When the Edit button is clicked under Output Table a table of Normalized
Current appears. The standard Lambda values appear in the Output column,
these numbers can be modified to reflect Air/Fuel ratio of a specific fuel. See

Appendix F for details of common fuels.

Custom tables can be saved using the Save As button.

CAN Collect Functionality

CAN Collect functionality allows one LTC (the CAN Collect Master) to collect
CAN data from up to 15 other slave LTCs, and retransmit these Lambda
readings on a single CAN address (see Appendix E – LTC CAN Messages).

Note: A CAN Collect Master device will continue to transmit the standard LTC
messages in addition to the special collect master messages.

CAN Collect functionality requires only a single CAN address to be configured
on a MoTeC Data Logger to receive up to 16 Lambda readings.

See Operation for information on configuring MoTeC Data Loggers or ECUs to
use CAN Collect.

Configure Master and Slave Units

• To configure an LTC as the CAN Collect Master device, select the CAN
Collect Master check box and select a CAN address.

The CAN address for the Master device is the address on which the
collected Lambda values will be retransmitted. This address must end in a
zero (i.e. hex 460, 470 etc). The recommended address is hex 460.

• To configure an LTC as a CAN Collect Slave device, clear the CAN
Collect Master check box and select a CAN address.

The CAN address for a Slave device must be configured with one of the 15
addresses following the master address. For example, if the collect master

MoTeC Configuration 13

address is hex 460, the slave devices must use CAN addresses in the
range hex 461 to 46F.

The Collect column on the main LTC
Manager Window shows the configuration
of CAN Collect Masters and Slaves. The
Master device is always shown as LTC
unit 1 (Master (1)), and the slave devices
are shown as LTC units 2 to 16 according
to the configured CAN address as shown
in this example.

Calibration

Warning: The Bosch LSU 4.9 Lambda sensors are fitted from factory with a

calibrated trimming resistor embedded in the sensor connector, if the factory
sensor connector is cut off and replaced with another type the LTC will not
operate correctly.

Note: Unlike the Bosch LSU 4.9 the NTK sensors standard connector can be

removed and replaced by a non-standard connector without affecting the
performance of the sensor or the LTC-N. However, the initial factory calibration
method will not work as the calibration resistor is built into the original
connector. In this case Free Air calibration is required. It is recommended that
no wiring modification is made to the NTK sensor or LTC-N unless completely
necessary.

Calibration Methods

Initial factory calibration

The default calibration method uses the known characteristics of a new
sensor that has been factory trimmed.

Free Air Calibration

As a sensor ages, the sensor calibration may change. To maintain accurate
readings, the LTC allows for re-calibration using the known oxygen
concentration of free air. The free air calibration procedure takes several
readings with the sensor in free air to calculate new calibration values.

To perform an accurate free air calibration, the lambda sensor must be
removed from the exhaust and placed in an open air environment.

It is recommended to perform the calibration outside of a workshop or dyno
room as there may be large amounts of hydrocarbons in the atmosphere.

14 Configuration

Contaminated air will result in an incorrect calibration or a failure to
calibrate. Wind should also be avoided as it can affect the free air
calibration.

Reference Gas Calibration

Reference gas samples for different lambda can be purchased (not
available from MoTeC) for use as a means of calibrating the LTC. This
method is provided for but is unlikely to be implemented by most users.

Calibrate the LTC Unit

• Click Calibrate… to open the Gain Calibration window

• Select one of the three options available.

o Select the Initial Factory Sensor Calibration check box. This is

the default value and can be used in most cases.

OR

Select the Entered Free Air Calibration check box and enter the
values in the boxes if a previous free air calibration value is known,

OR

Select the Free Air Calibration check box to perform a new
calibration.

− Click Perform Air Calibration
Note: The calibration process may take several minutes during

which the calibration progress window is displayed.

− When the message Calibration completed appears click OK

− The new calibration value is displayed. This value should be

recorded against the serial number of the sensor to enter this
calibration when the sensor is used with another LTC unit.

− To apply the new calibration click OK.

• Click OK to save the calibration method and settings to the LTC.

Tip: Spare sensors can be air calibrated before an event and tagged with the
14 digit calibration number. This number can be used in the entered Free Air
Calibration option for quick replacement of a sensor during the event.

MoTeC Configuration 15

Calibrate the LTC-N Unit

• Click Calibrate… to open the Gain Calibration window

• Select one of the four options available.

o Select the Initial Factory Sensor Calibration check box. This is

the default value and can be used in most cases.

OR

Select the Entered Gain Factor from a previous Free Air Calibration
or Reference Gas Calibration

OR

Select the Free Air Calibration check box to perform a new
calibration.

− Click Perform Air Calibration
Note: The calibration process may take several minutes during

which the calibration progress window is displayed.

− When the message Calibration completed appears click OK

− The new calibration value is displayed. This value should be

recorded against the serial number of the sensor to enter this
calibration when the sensor is used with another LTC unit.

− To apply the new calibration click OK.

OR

Select the Reference Gas Calibration.

Note: A Reference Gas Calibration is not recommended for normal
use as it required calibrated testing gas.

• Click OK to save the calibration method and settings to the LTC.
Tip: Spare sensors can be air calibrated before an event and tagged with the 4

digit calibration number. This number can be used in the Entered Gain Factor
calibration option for quick replacement of a sensor during the event.

16 Configuration

Firmware

Each version of the LTC Manager software includes a matching firmware
version that must be sent to the LTC in order to operate correctly.

The Config Status column in the main LTC Manager window will indicate if the
firmware version requires updating.

Update the Firmware

• Select the LTC row in the main LTC Manager window

• Click Update Firmware.

A progress window will be displayed while the firmware is sent to the LTC.

MoTeC Operation 17

Operation

Monitoring LTCs

The main LTC Manager window shows live readings, diagnostics and LTC
state information for all connected LTCs.

Serial Num

The Serial Num column shows the unique serial numbers of all connected
LTCs. An LTCD will be displayed as two LTCs with the same serial number but
the designators A and B to identify the two sensors.

Name

The Name column shows the assigned names of all connected LTCs. The
displayed name is configured in the Setup dialog. The LTC rows in the main
screen are sorted by the name column.

Readings

The Readings column shows live readings of all connected LTCs. The
readings can be configured to display as either Lambda or AFR (Air Fuel Ratio)
for a number of different fuels.

Note: the display units do not affect the units of the transmitted readings in
CAN messages.

Configure display units

• Select Tools > Options.

18 Operation

• Choose a predefined stoichiometric AFR for one of various fuels
OR

Define a custom AFR by entering a stoichiometric point between 1.0 and

100.0.

Display live readings in larger format

• Select View > Readings or press F5.

This larger format display provides a useful means of monitoring several
sensor values while tuning.

Sensor State

The Sensor State column shows the operating state of all connected LTCs.

Sensor State Description

Starting LTC hardware is performing a self calibration

Heating The Lambda sensor is outside the temperature range

required for measurement

Running Lambda measurement is active

Cooling A heater short circuit or a failure to reach operating

temperature has occurred. The sensor is allowed to
cool before another attempt at heating.

MoTeC Operation 19

Diagnostics

The Diagnostics column shows faults and diagnostic information for all
connected LTCs.

Diagnostic Description

Heater short
circuit (GND)

Heater short
circuit (Batt+)

Heater open
circuit

Failed to achieve
heat

Sensor short
circuit

Corrupt Firmware The LTC firmware is corrupt. Upgrade the firmware to

Incompatible
Firmware

A short circuit to ground has been detected in the
heater wiring

A short circuit to battery+ has been detected in the
heater wiring

An open circuit has been detected in the heater wiring

The measured sensor temperature is not responding
to sensor heating. This fault may indicate a fault with
the sensor wiring.

A short circuit has been detected in the sensor wiring

restore operation.

The LTC firmware is incompatible with LTC Manager.
Upgrade the firmware to restore operation.

LTC Temp

The LTC Temp column shows live internal temperature readings of all
connected LTCs.

Note: The temperature column shows the temperature of the LTC unit, not the
sensor temperature.

CAN Address

The CAN Address column shows the configured CAN addresses (in hex) of all
connected LTCs.

To configure the CAN addresses see Setup.

Collect

The Collect column shows the configured CAN Collect functionality of all
connected LTCs. To configure the CAN Collect functionality see Setup.

A configured CAN Collect Master device is always shown as Master (1).

20 Operation

Any LTC unit configured with a CAN address within the 15 CAN addresses
following a Collect Master address will be shown as Slave (x).

The number in the collect column (e.g. (3)) refers to the LTC number (1 to 16)
in the messages transmitted by a Collect Master LTC.

For more information about CAN Collect, see

CAN Collect Functionality

Config Status

The Config Status column shows any issues relating to the configuration of the
connected LTCs.

Config Status Description

OK Config is OK

Disabled The LTC has been disabled under the Setup options.

A disabled LTC will not measure or transmit readings.

Incompatible
Config

Corrupt Config The configuration in the LTC is corrupt. A new

CAN Address
Conflict

The configuration in the LTC is not compatible with
the firmware in the LTC. A new configuration can be
sent to the LTC by changing the Setup or Calibration.

configuration can be sent to the LTC by changing the
Setup or Calibration.

Multiple LTC units have been configured with the
same CAN address. Each LTC must be configured
with a unique address.

Firmware Version

The Firmware Version column shows the version of the firmware in each of the
connected LTCs.

MoTeC Data Loggers

MoTeC Data Loggers SDL, SDL2, ADL2, ADL3 and ACL include CAN
communication templates to receive LTC messages from up to 16 LTCs.

Received Lambda readings and diagnostics can be displayed and logged.
Refer to the Dash Manager software for more information.

Configure Data Logger Communications for LTC:

• Select Inputs > Communications

MoTeC Operation 21

• Click on an unused CAN row in the Communication Sections

• Click Select button and choose a template

o Select the matching template (e.g. LTC #1 (CAN ID 460)) to receive

all available readings and diagnostics from an LTC. The selected
template must match the LTC CAN address specified in LTC
Manager.
Receiving full LTC messages provides the most information about
an LTC and requires one CAN section per LTC in the
communications setup.

o Select the LTC Collect 16 Channel CAN template to receive

Lambda readings from up to 16 LTCs. The LTCs must be
configured in LTC Manager for CAN Collect functionality using
address hex 460 for the CAN Collect Master.
Receiving CAN collect messages provides only Lambda readings
from each LTC and only requires one CAN section in the
communications setup for up to 16 Lambda readings.
For more information see

CAN Collect Functionality.

MoTeC 'Hundred Series' ECUs

MoTeC ‘Hundred Series’ ECUs (M400, M600, M800, M880) can be configured
to receive Lambda measurements from up to 12 LTCs using the existing PLM
CAN templates in the ECU Manager software. The M84 ECU can receive two
channels of Lambda with CAN addresses 460 and 461.

Received Lambda readings can be used in engine control and logged.
Refer to the ECU Manager software for more information.

Note: The ECU only stores the Lambda readings from the LTC messages;
LTC diagnostic information is not stored.

Configure Hundred Series ECU Communications for LTC

• Select Adjust > General Setup > Communication > CAN Setup

• For single LTC configuration:

o Select a spare CAN data slot in the range CAN 1 to CAN 6
o Enter 1 - PLM Receive for CAN Data

Enter the LTC CAN Address in decimal*
the CAN address specified in LTC Manager.

• For CAN Collect configuration:
The LTCs must be configured in LTC Manager for CAN Collect
functionality using address hex 460 for the CAN Collect Master.

. The address must match

22 Operation

o Enter 1 - PLM Receive for CAN 6 Data
o Enter the LTC CAN address in decimal*

The address must match the CAN address specified in LTC
Manager for the CAN Collect Master LTC. The recommended
address is 1120.

* Important: CAN addresses in ECU Manager are in decimal, while the CAN
addresses in LTC Manager are in hex. e.g. 1120 decimal = 460 hex

for CAN 6 address.

Configure M84 ECU Communications for LTC

• Select Adjust > General Setup > Communication > CAN Setup

• For single or dual LTC configuration:

o Enter a CAN Address of 1120 (460 Hex) into the PLM CAN

Address

Assign Lambda measurements to a Hundred Series channel

Lambda measurements from the LTCs must be assigned to an ECU channel
before they can be used for engine control or logging.

• Select Adjust > Sensor Setup > Input Setup... to open the Input Pins Setup
dialog.

• Attach an LTC reading to a channel, using the following parameters

Input Source Predefined Calibration

PLM 1 to PLM 12 #81 Lambda: PLM over CAN

Example 1: LTC1 reading assigned to channel Lambda 1

MoTeC Operation 23

Example 2: LTC1 to LTC4 readings assigned to Lambda Cyl channels

Assign Lambda measurements to a M84 channel

For an M84 the Lambda Input Source is fixed so only the Calibration needs to
be chosen – Predefined “#81 Lambda: PLM over CAN”

24 Operation

Lambda and Air Fuel Ratio

Lambda gives a measure of the Air to Fuel Ratio (AFR) that is independent of
the type of fuel being used.

Lambda 1.00 Stoichiometric ratio: no excess fuel and no excess air

Lambda > 1.00 Lean: excess air

Lambda < 1.00 Rich: excess fuel

Stoichiometric Air Fuel Ratio for various fuels

Lambda Air Fuel Ratio

Petrol Alcohol LPG Diesel

1.0 14.7 6.4 15.5 14.5

Calculations with Lambda

Fuel Stoichiometric

AFR

Petrol 14.7 AFR = 14 Lambda = 14/14.7 = 0.95

Diesel 14.5 Lambda = 1.1 AFR = 1.1 x 14.5 = 16

See Appendix F – Lambda to Air Fuel Ratio Table for a quick reference table.

Measured
value

Calculated value

Engine Tuning with Lambda

When tuning the engine, the target Lambda (or AFR) is dependent on the
tuning objective. The following table can be used as a guideline.

Tuning objective Lambda

Maximum power 0.84 to 0.90

Economy 1.05

Emissions 1.00

Normally the engine is tuned for maximum power at full load and for emissions
or economy at light loads.

The exact requirements for a specific engine and fuel can only be found by
experimentation. On turbo engines extra fuel may be desirable to reduce
exhaust temperatures and help avoid knock. If the vehicle is fitted with a
catalytic converter, extra fuel may be required to ensure the catalyst does not
overheat when not operating at Lambda 1.00

MoTeC Operation 25

Lambda Sensor

Sensor Warm-up

The internal heater in the Lambda sensor is powerful enough to allow accurate
measurement when gas temperature is at room temperature. The sensor will
take approximately 20 seconds to heat up.

The maximum continuous operating temperature of the sensor is 850 °C.
Sensors should not be used at higher temperatures for a prolonged period,
although the sensor can be heated to 930 °C for a maximum of 10 minutes.
This may however reduce the accuracy.

Sensor Lifetime

The sensor lifetime is dependent on the type of fuel being used and the volume
of gas flow over the sensor.

Sensor lifetime will be reduced by contaminants such as silicon, lead, oil, etc.
Thermal cycling and exposure to exhaust fumes without any heating control
active will also age the sensor more rapidly.

Manifold sealants can contaminate sensors. Use sealants that are sensor­friendly to prevent reduced sensor lifetime.

When using leaded fuel, sensor element contamination will reduce the sensor
lifetime substantially. Typically sensor lifetime for high performance engines is
at least 500 hours in unleaded fuel and 50 hours in leaded fuel. Longer
lifetimes can be expected for less demanding applications. These figures are a
conservative estimate as the sensors are designed to be accurate for 50,000
km of operation in a road car.

Incorrect placement in the exhaust can overheat the sensor and significantly
reduce the sensor life. For the Bosch LSU 4.9 the sensor impedance (Ri) is an
indication of sensor temperature. In normal operation Ri should be
approximately 300 ohms. If Ri is less than 250 ohms then the sensor is being
overheated. Ri is included in the transmitted CAN messages. Due to the
different control system for the NTK sensor the Ri parameter is not applicable.

At the end of its life the sensor becomes slow to respond and does not read
rich properly. Regular performance of the Free Air Calibration (see Calibration)
will maintain the accuracy of the sensor over its lifetime.

26 Operation

LTC Operating Tips

If the engine misfires for any reason, including an over-rich mixture, the LTC
may falsely read Lean. This is due to excess air being present in the exhaust
gasses, caused by incomplete combustion.

Other areas that can give misleading readings include at high RPM, closed
throttle when the mixture won’t burn completely. Following overrun fuel cut
when the sensor has become saturated with oxygen it can take up to several
seconds to resume accurate readings. Engine misfires include hitting the rev­limiter, be it a fuel or ignition cut or a combination of both, and can give a
similar result with time being required to purge the sensor of excess oxygen or
fuel.

Engines with high overlap camshafts running at low speed may pump air
through the engine resulting in a false lean reading, Therefore the LTC may
need to read leaner than would otherwise be expected.

MoTeC Appendices 27

Appendices

Appendix A – Specifications

Sensor Type

Power Supply

Communications

Physical

Max Temperatures

• Bosch LSU 4.9 Lambda sensor (LTC4.9)

• NTK LZA09 Lambda Sensor

• 11 V - 16 V DC

• 110 mA typical current plus the sensor heater

current.

• Heater current is typically 0.5 A - 1 A (up to 2 A
on startup)

• 1 Mbit/sec CAN

• Dimensions 38 x 26 x 14 mm excluding wiring

looms and connectors

• Weight 62 grams

• Mounting holes spacing 32 mm (Ø3.2 mm)

• Max ambient temperature at device 100 °C

• Max internal device temperature 125 °C

28 Appendices

Appendix B – Pinout

Bosch LSU version (LTC 4.9)

LTC Connector A
LTCD Connector A and B

Bosch LSU 4.9 sensor connector
Mating connector: supplied on sensor

Pin No Wire Colour Description

1 Red Ip

2 Yellow Sensor 0 V

3 White Heater -

4 Grey Heater +

5 Green Ipr

6 Black Vs

Power/CAN Connector

DTM 4pin (M) (#68055)
Mating connector: DTM 4pin (F) (#68054)

Pin No Wire Colour Description

1 Black Battery -

2 Green CAN Lo

3 White CAN Hi

4 Red Battery +

MoTeC Appendices 29

NTK version (LTC-N)

LTC-N Connector A

NTK sensor connector
Mating connector: supplied on sensor

Pin No Wire Colour Description

1 Blue Heater +

2 Yellow Heater -

3 Orange Rc

4 Black Sensor 0V

5 N/C

6 Grey VS

7 White IP

8 Black Sensor 0V

Power/CAN Connector

DTM 4pin (M) (#68055)
Mating connector: DTM 4pin (F) (#68054)

Pin No Wire Colour Description

1 Black Battery -

2 Green CAN Lo

3 White CAN Hi

4 Red Battery +

30 Appendices

Appendix C – Dimensions

MoTeC Appendices 31

32 Appendices

MoTeC Appendices 33

Appendix D – Wiring Details

To connect a single LTC unit, the Power/CAN Connector pins should be wired
according to the following table, taking into account general CAN bus wiring
requirements:

LTC/LTC-N Pin

SDL & SDL3
(CAN 0)

SDL3 (CAN 1) 29 30
ADL2 73,75 74,76
ADL3 (CAN 0) 73 74
ADL3 (CAN 1) 75 76
ACL (CAN 0) 5 6
ACL (CAN 1) 7 8
M84 B24 B23
M400/M600/M800 B24 B23
M880 47 48

Tip: To wire the LTC to power, connect either to the ignition switch for fast
sensor start up or connect to the fuel pump relay to prevent accidental battery
drainage

Battery - CAN Lo CAN Hi Battery +

1 2 3 4

35 36

Ground

Power 12 V (see tip)

For wiring a CAN bus with several LTCs and any number of other CAN
devices refer to the example below.

PC Connection

The LTC connects to the USB port on the PC via a MoTeC UTC (USB to
CAN). The UTC is plugged into a CAN connector wired into the CAN bus.

Wiring Loom Connection

Care must be taken for power and ground wiring for the LTC. Each sensor
can draw over 3 Amps when cold if multiple channels of Lambda are used this
current draw will increase dramatically. Wiring size should be suitable for the
number of LTCs used.

34 Appendices

General CAN Bus Wiring Requirements

The CAN bus should consist of a twisted pair trunk with 100R terminating
resistors at each end. The preferred cable for the trunk is 100R data cable.
The maximum length of the bus is 16 metres (50 ft)

CAN devices (such as MoTeC Data Loggers, ECUs etc) may be connected to
the trunk with up to 500 mm (20 in) of twisted wire.

The CAN connector for the UTC may also be connected to the trunk with up to
500 mm (20 in) of twisted wire and should be within 500 mm of one end of the
trunk.

If desired, two CAN connectors may be used so that the MoTeC UTC may be
connected to either side of the vehicle. Each connector must be within 500
mm of an end of the trunk.

Short CAN Bus

If the CAN bus is less than 2 meter (7 ft) long, a single termination resistor
may be used. The resistor should be placed at the opposite end of the CAN
bus to the CAN connector.

MoTeC Appendices 35

CAN-LO

CAN-HI

CAN

-

LO

CAN

-

HI

500mm

Max

CAN

-

LO

CAN

-

HI

CAN

500mm

Max

<< CAN Bus >>

CAN

-

LO

CAN

-

HI

CAN

-

LO

CAN

-

HI

543

1

100R Terminating
Resistors at each
end of the CAN Bus

100R

CAN

Device

These w ires must be twisted

Minimum one twist per 50mm (2in)

CAN

Device

CAN

Device

Connector

0V
8V

100R

500mm Max

36 Appendices

Appendix E – LTC CAN Messages

Messages 1 and 2 are transmitted by all LTC units.
Messages 5 to 10 are only transmitted from an LTC unit configured as a CAN
Collect Master.

Message 1

Byte Name Scaling

0 Compound ID = 0 N/A
1:2 Lambda Hi:Lo = x.xxxLa

3:4

5 LTC Internal Temperature

6 Fault bits

7 Heater duty cycle xxx%

Ipn (Normalised pump cell
current)

Hi:Lo = xxxx µA

xxx °C
Heater short to Gnd
Heater short to VBatt
Heater open circuit
Heater failed to heat
Sensor wire short

Bit 0
Bit 1
Bit 2
Bit 3
Bit 4

Message 2

Byte Name Scaling

0 Compound ID = 1 N/A

START
DIAGNOSTICS
PRE CAL
CALIBRATION

1 Sensor State

2:3 Battery Voltage Hi:Lo = x.xxV
4:5 Ip (Raw pump cell current) Hi:Lo = xxxx µA

6:7

Ri (Sensor cell impedence)
(0 for LTC-N, not applicable)

POST CAL
PAUSED
HEATING
RUNNING
COOLING

Hi:Lo = xxxx Ohms

0
1
2
3
4
5
6
7
8

MoTeC Appendices 37

Message 3

Byte Name Scaling

0 Compound ID = 2 N/A

A

1 Firmware Version Letter

2:3 Firmware Version Number e.g. 104 = v1.04
4:5 Serial Number

B
C

0
1
2

Message 5

Byte Name Scaling

0 Compound ID = 4 N/A
1 Reserved N/A
2:3 LTC1 (Master LTC) Lambda Hi:Lo = x.xxxLa
4:5 LTC2 Lambda Hi:Lo = x.xxxLa
6:7 LTC3 Lambda Hi:Lo = x.xxxLa

Message 6

Byte Name Scaling

0 Compound ID = 5 N/A
1 Reserved N/A
2:3 LTC4 Lambda Hi:Lo = x.xxxLa
4:5 LTC5 Lambda Hi:Lo = x.xxxLa
6:7 LTC6 Lambda Hi:Lo = x.xxxLa

Message 7

Byte Name Scaling

0 Compound ID = 6 N/A
1 Reserved N/A
2:3 LTC7 Lambda Hi:Lo = x.xxxLa
4:5 LTC8 Lambda Hi:Lo = x.xxxLa
6:7 LTC9 Lambda Hi:Lo = x.xxxLa

Message 8

Byte Name Scaling

0 Compound ID = 7 N/A

38 Appendices

1 Reserved N/A
2:3 LTC10 Lambda Hi:Lo = x.xxxLa
4:5 LTC11 Lambda Hi:Lo = x.xxxLa
6:7 LTC12 Lambda Hi:Lo = x.xxxLa

Message 9

Byte Name Scaling

0 Compound ID = 8 N/A
1 Reserved N/A
2:3 LTC13 Lambda Hi:Lo = x.xxxLa
4:5 LTC14 Lambda Hi:Lo = x.xxxLa
6:7 LTC15 Lambda Hi:Lo = x.xxxLa

Message 10

Byte Name Scaling

0 Compound ID = 9 N/A
1 Reserved N/A
2:3 LTC16 Lambda Hi:Lo = x.xxxLa
4:5 Reserved N/A
6:7 Reserved N/A

MoTeC Appendices 39

Appendix F – Lambda to Air Fuel Ratio Table

Lambda

0.70 10.3 4.5 10.9 10.2

0.75 11.0 4.8 11.6 10.9

0.80 11.8 5.1 12.4 11.6

0.85 12.5 5.4 13.2 12.3

0.90 13.2 5.8 14.0 13.1

0.95 14.0 6.1 14.7 13.8

1.00 14.7 6.4 15.5 14.5

1.05 15.4 6.7 16.3 15.2

1.10 16.2 7.0 17.1 16.0

1.15 16.9 7.4 17.8 16.7

1.20 17.6 7.7 18.6 17.4

1.25 18.4 8.0 19.4 18.1

1.30 19.1 8.3 20.2 18.9

1.35 19.8 8.6 20.9 19.6

1.40 20.6 9.0 21.7 20.3

1.45 21.3 9.3 22.5 21.0

1.50 22.1 9.6 23.3 21.8

1.55 22.8 9.9 24.0 22.5

1.60 23.5 10.2 24.8 23.2

Petrol Alcohol LPG Diesel

Air Fuel Ratio