Diagnostic Routine AD
Diagnostic Routine AD
Diagnostic Overview
The Reversing Lamps Are On Continuously
Refer to Wiring Diagram Set 93 for schematic and connector information Electrical Diagrams.
Normal Operation and Fault Conditions
REFER to Reversing Lamps - Automatic Transmission .
REFER to Reversing Lamps - Manual Transmission .
Pinpoint Test
1. CHECK THE PCM (Powertrain Control Module) REVERSE GEAR PID (Parameter Identification)
1. Make sure the transmission is in park (automatic) or neutral (manual).
2. Ignition ON.
3. Using a scan tool, view TCM (Transmission Control Module) (automatic transmission) or PCM (Powertrain Control Module) (manual transmission) PIDs (Parameter Identifications).
4. For vehicles equipped with an automatic transmission, monitor the TCM (Transmission Control Module) GEAR_ENGAGED PID (Parameter Identification).
5. For vehicles equipped with a manual transmission, monitor the PCM (Powertrain Control Module) REV_SW PID (Parameter Identification).
Does the PID (Parameter Identification) indicate the transmission is in reverse gear?
2. CHECK THE REVERSING LAMP SWITCH
1. Ignition OFF.
2. Disconnect: Reversing Lamp Switch.
3. Ignition ON.
4. Monitor the PCM (Powertrain Control Module) REV_SW PID (Parameter Identification).
Does the PID (Parameter Identification) indicate the transmission is in reverse gear?
3. CHECK THE REVERSING LAMP SWITCH INPUT CIRCUIT FOR A SHORT TO GROUND
1. Ignition OFF.
2. Disconnect: PCM (Powertrain Control Module) C175B.
3. Measure:
Is the resistance greater than 10,000 ohms?
4. CHECK THE REVERSING LAMPS SUPPLY CIRCUIT FOR A SHORT TO VOLTAGE
1. Ignition OFF.
2. Disconnect: BCM (Body Control Module) C2280E.
3. Ignition ON.
Does either reversing lamp continue to illuminate?
5. CHECK FOR CORRECT PCM (Powertrain Control Module) OPERATION
1. Disconnect and inspect all PCM (Powertrain Control Module) connectors.
2. Repair:
- corrosion (install new connector or terminals- clean module pins)
- damaged or bent pins- install new terminals/pins
- pushed-out pins- install new pins as necessary
3. Reconnect the PCM (Powertrain Control Module) connectors. Make sure they seat and latch correctly.
4. Operate the system and determine if the concern is still present.
Is the concern still present?
6. CHECK FOR CORRECT BCM (Body Control Module) OPERATION
1. Disconnect and inspect all BCM (Body Control Module) connectors.
2. Repair:
- corrosion (install new connector or terminals- clean module pins)
- damaged or bent pins- install new terminals/pins
- pushed-out pins- install new pins as necessary
3. Reconnect the BCM (Body Control Module) connectors. Make sure they seat and latch correctly.
4. Operate the system and determine if the concern is still present.
Is the concern still present?
