Grand Caravan FWD V6-3.3L VIN 3 Flex Fuel (2002)
damage to it. The FCM will re-activate control of the relay after a 25 second cool-down period. This circuit is electronically controlled and
continuously monitored for malfunctions.
Front and Rear Blower Relay
The blower control switch is part of the Automatic Temperature Control (ATC) or A/C-Heater Control Module, (Manual Temp). When the blower
switch is turned on, the ATC or A/C-Heater Control Module sends a PCI Bus message to the FCM. The front and rear blower relay is then powered
through low side control on pin 30 of the FCM. The relay provides the high side to the blower motor, and the blower speed is governed through low
side control in the ATC or A/C-Heater Control Module. This circuit is electronically controlled and continuously monitored for malfunctions.
Name Brand Speakers (NBS) Relay
The NBS relay operates through the vehicle bus interface between the radio and the FCM. When the radio is turned on, the radio sends a PCI Bus
message to the FCM. The NBS relay is then powered on through low side control on pin 11 of the FCM. The relay supplies power to the amplified
speaker, and ground is supplied through the radio. This circuit is electronically controlled and continuously monitored for malfunctions.
Electronic Back Light (EBL) Relay
The rear defrost switch is part of the Automatic Temperature Control or A/C-Heater Control Module (Manual Temp). when the ignition switch is in
the RUN position and the rear defrost switch is turned on, the ATC or A/C-Heater Control Module sends a PCI Bus message to the FCM. The EBL
run only relay is then powered through low side control on pin 31 of the FCM. The relay provides the high side to the rear window defrost grid, and
ground is attached to the vehicle body. The FCM will only allow the rear defrost to operate in the RUN position. This circuit is electronically
controlled and continuously monitored for malfunctions.
Electrical Inputs
ELECTRICAL INPUTS
Headlamp battery supplies 1 & 2 - 12 volt input on pins 1 and 2. Battery supply voltage for switching headlamp circuits only.
Module battery supply - 12 volt input on pin 9. Battery supply voltage for all other FCM operations.
Power ground - Ground source on pin 8 for all FCM operations.
Ignition switch RUN or START position status - 12 volt input on pin 37. Allows the FCM to determine the ignition switch status for related FCM
operations.
Ignition switch START only status - 12 volt input on pin 19. Allows the FCM to discriminate between RUN/START input and START for related
FCM operations.
PCI Bus - Approximately 7.5 volt input on pin 22. Allows the FCM to communicate with other modules on the vehicle bus.
Stop lamp Switch status - 12 volt input on pin 44. Provides for brake shift interlock function.
Horn Switch - Ground input on pin 17. Primary means for engaging the horn.
Back-up switch - Ground input on pin 39. Input is converted to a PCI Bus status message for use by other modules.
Wiper park switch - Ground input on pin 16. Used to determine park placement of wipers. Also used as feedback to FCM to determine correct
operating mode of wipers.
Washer fluid level switch - Ground input to pull-up on pin 18. Ground is switched into the circuit when washer bottle fluid level is low.
Brake fluid level switch - Ground input to pull-up on pin 36. Ground is switched into the circuit when brake fluid level is low.
Ambient temperature sensor - Resistive input to pull-up on pin 25. Corresponding voltage level is converted to a PCI Bus message for use by other
modules on the bus.
Right park lamp outage - 12 volt input on pin 21. Used to determine if right park lamp circuit is operating properly.
Left park lamp outage - 12 volt input on pin 41. Used to determine if left park lamp circuit is operating properly.
Battery IOD - 12 volt input on pin 20. The FCM enters a low power consumption mode when the ignition is turned OFF. This low current draw
battery supply keeps the microprocessor functioning in the low power mode.
Battery (+) connection detection - 12 volt input on pin 38. The battery connection on the PDC incorporates the use of an internal switch to determine
if the connector is properly mated and the Connector Positive Assurance (CPA) is engaged. If the CPA is not properly engaged, a voltage on pin 38
will be interpreted as an unseated connector and a fault will set.
