B166B
B166B-LEFT TRAILER TOW LAMP CONTROL CIRCUIT LOWB166B - Left Trailer Tow Lamp Control Circuit Low:
WHEN MONITORED
With the Trailer Tow Lamps activated.
SET MONITORED
When the FCM detects a LOW condition.
POSSIBLE CAUSES
- (L655) Trailer tow control circuit
- Front control module
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.
Diagnostic Test
1. INTERMITTENT CONDITION
Turn the ignition on.
With the Scan Tool, clear all FCM DTC's.
Turn the Trailer Tow Lamps on.
With the Scan Tool read the DTC information.
Q: Does the Scan Tool read: B166B-LEFT TRAILER TOW LAMP CONTROL CIRCUIT LOW?
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 the BODY VERIFICATION TEST - VER 1. Body Verification Test
2. (L655) TRAILER TOW CONTROL CIRCUIT
Turn the ignition off.
Disconnect the FCM PDM harness connector.
Measure the resistance between ground and the (L655) Left Trailer Tow Control circuit.
Q: Is the resistance below 5.0 ohms?
YES: Replace the Front Control Module (FCM). Perform the BODY VERIFICATION TEST VER1.
NO: Repair the (L655) Left Trailer Tow Control circuit for a short to ground condition. Perform the BODY VERIFICATION TEST VER1.