Dodge Ram Truck 1500-2500-3500. Manual — part 423

FCM-RIGHT TRAILER RELAY OUTPUT CIRCUIT OPEN

8L - 98

LAMPS/LIGHTING - EXTERIOR - ELECTRICAL DIAGNOSTICS

DR/DH

FCM-RIGHT TRAILER RELAY OUTPUT CIRCUIT OPEN (CONTINUED)

For the Exterior Lighting system circuit diagram (Refer to 8 - ELECTRICAL/LAMPS/LIGHTING - EXTERIOR -
SCHEMATICS AND DIAGRAMS).

For a complete wiring diagram Refer to Section 8W.

•

When Monitored:
With the ignition on

•

Set Condition:
The FCM detects an open condition

Possible Causes

INTEGRATED POWER MODULE

FRONT CONTROL MODULE

TRAILER LAMP RELAY OUTPUT CIRCUIT OPEN

1.

INTERMITTENT CONDITION

Turn the ignition on.

With the DRBIII

T

, clear all FCM DTC’s.

Actuate the Trailer Tow Lamps.

With the DRBIII

T

, read the DTC information.

Does the DRBIII

T

read: Right Trailer Relay Out-

put Circuit Open?

Yes

>> Go To 2

No

>> The condition that caused the symptom is

currently not present. Inspect the related
wiring for a possible intermittent condition.
Look for any chafed, pierced, pinched, or
partially broken wires.

Perform BODY VERIFICATION TEST -
VER 1.

2.

INTEGRATED POWER MODULE

Turn the ignition off.

Check the IPM to make certain the Right Trailer Tow Relay is present.

Is the Trailer Tow Relay present?

Yes

>> Go To 3

No

>> Replace the Integrated Power Module.

Perform BODY VERIFICATION TEST - VER 1.

DR/DH

LAMPS/LIGHTING - EXTERIOR - ELECTRICAL DIAGNOSTICS

8L - 99

FCM-RIGHT TRAILER RELAY OUTPUT CIRCUIT OPEN (CONTINUED)

3.

FRONT CONTROL MODULE

Turn the ignition off

Measure the voltage of the Fused B+ circuit of the Trailer Tow relay in
the IPM.

Is the voltage above 10 volts?

Yes

>> Replace the Front Control Module.

Perform BODY VERIFICATION TEST - VER 1.

No

>> Repair the Trailer Lamp Relay Output Circuit.

Perform BODY VERIFICATION TEST - VER 1.

8L - 100

LAMPS/LIGHTING - EXTERIOR - ELECTRICAL DIAGNOSTICS

DR/DH

MIC-TURN HAZARD SWITCH INPUT CIRCUIT OPEN

DR/DH

LAMPS/LIGHTING - EXTERIOR - ELECTRICAL DIAGNOSTICS

8L - 101