MSD 8739 Installation
Module 2 This is the default module. It is active when no voltage is present
on the other wires.
Active when 12 volts are applied to the Red Wire.
Active when 12 volts are applied to the Blue Wire. (3-Step Only)
Module 1
Note: If 12 volts are applied to the Red and Blue wires at the same time, Module 3
will be active.
Module 3
ACTIVATION WIRES
SWITCH OR
MICRO SWITCH
PN 8820
TO GROUND
TO 12V
RED
BLACK
TO MODULE SOCKET
TO LINE LOCK
OR TRANS-BRAKE
SOLENOID
MODULE SELECTOR
STEP
MODULE 2 MODULE 1
PN 8739
AUTOTRONIC CONTROLS CORPORATION
1490 HENRY BRENNAN DR, EL PASO, TX 79936
TM
MSD Module Selectors
Two Step, PN 8739
Three Step, PN 8737
ONLINE PRODUCT REGISTRATION: Register your MSD product online and you’ll be entered
in our monthly 8.5mm Super Conductor Spark Plug Wire give-away! Registering your product
will help if there is ever a warranty issue with your product and helps the MSD R&D team create
new products that you ask for! Go to www.msdignition.com/registration.
Parts Included:
1 - Module Selector
1 - Parts Bag, Wiring Terminals
4 - Mounting Screws
Note: Do NOT use solid core spark plug wires with any MSD component.
The MSD Module Selectors provide the ability to switch between two or three different rpm or degree
modules. The different modules are activated when 12 volts are applied to the corresponding activation wire. The Selectors work with either a Soft Touch Rev Control or any MSD Timing Control that
uses plug-in modules.
•The 2-Step Module Selector switches between two modules.
•The 3-Step Module Selector switches between three modules.
M S D • W W W . M S D P E R F O R M A N C E . C O M • ( 9 1 5 ) 8 5 7 - 5 2 0 0 • F A X ( 9 1 5 ) 85 7 - 3 3 4 4
Figure 1 Basic Two Step Module Selector Installation.
2 INSTALLATION INSTRUCTIONS
T
A
C
H
C+
C-
IGN
PTS
M+
M-
GROUND
RPM
TO GROUND
TO 12V
MODULE 2 - ACTIVE WITH NO VOLTAGE.
MODULE 1 - ACTIVE WITH 12 VOLTS ON RED WIRE.
MODULE 3 - ACTIVE WITH 12 VOLTS ON BLUE WIRE. THIS
MODULE WILL ALSO BE ACTIVE IF 12 VOLTS
ARE SUPPLIED TO THE RED AND BLUE WIRES.
TO 12V
CLUTCH SWITCH
MSD MICRO SWITCH
PN 8820
BLUE
RED
BLACK
TO LINE LOCK
OR TRANS-BRAKE
SOLENOID
MODULE 2 MODULE 1
PN 8737
MODULE SELECTOR
3
MODULE 3
AUTOTRONIC CONTROLS CORPORATION
1490 HENRY BRENNAN DR, EL PASO, TX 79936
TM
BLACK
TO
GROUND
RELAY
PN 8961
RED
JUMPER
(+) 12V
CLUTCH
SWITCH
LINE LOCK
SOLENOID
REV LIMITER
(+) 12V
IF YOUR APPLICATION REQUIRES USING THE CLUTCH FOR EVERY SHIFT,
THIS DIAGRAM WILL PROVIDE A REV LIMIT ON THE LAUNCH ONLY AND
HOLD THE LINE LOCK ON UNTIL THE CLUTCH PEDAL IS RELEASED.
MOMENTARY
PUSH BUTTON
SWITCH
TO
GROUND
TO
GROUND
MODULE SELECTOR
STEP
MODULE 2 MODULE 1
PN 8739
AUTOTRONIC CONTROLS CORPORATION
1490 HENRY BRENNAN DR, EL PASO, TX 79936
TM
87A
87
NO
NC
C
86
85
30
Figure 2 Wiring a Two Step to a Latching Relay.
M S D • W W W . M S D P E R F O R M A N C E . C O M • ( 9 1 5 ) 8 5 7 - 5 2 0 0 • F A X ( 9 1 5 ) 85 7 - 3 3 4 4
Figure 3 Basic Three Step Installation.
Loading...