Pinpoint Test X: The Reversing Lamps Are Inoperative
Reversing Lamps
Pinpoint Test X: The Reversing Lamps Are Inoperative
Normal Operation
The PCM monitors the transaxle gear status. When the PCM detects the transaxle in REVERSE (R), the PCM provides ground for the reversing lamps relay coil.
Voltage is supplied from the Battery Junction Box (BJB) fuse 46 (15A) to the coil side of the reversing lamps relay. When the reversing lamps relay is energized, voltage is routed to the reversing lamps.
- DTC P1910 (Reverse Lamp Control Circuit/Open)- sets when the PCM detects no voltage from the reversing lamp relay coil ground control circuit (if the coil voltage supply circuit or the coil ground control circuit is open).
This pinpoint test is intended to diagnose the following:
- Fuse
- Wiring, terminals or connectors
- Reversing lamps relay
- PCM
PINPOINT TEST X : THE REVERSING LAMPS ARE INOPERATIVE
NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
X1 CHECK FOR PCM TR (Transmission Range) SENSOR DTCs FROM THE SELF-TEST
- Review the DTCs from the PCM Key ON Engine OFF (KOEO) self-test.
Are any Transmission Range (TR) sensor DTCs present?
Yes
REFER to Automatic Transmission/Transaxle &/or Transmission Control Systems.
No
GO to X2.
X2 CHECK THE REVERSING LAMPS RELAY
- Ignition OFF.
- Disconnect: Reversing Lamps Relay.
- Ignition ON.
- Substitute a known good relay and recheck the reversing lamps operation.
Do the reversing lamps operate correctly?
Yes
REMOVE the known good relay. INSTALL a new reversing lamps relay. TEST the system for normal operation.
No
REMOVE the known good relay. GO to X3.
X3 CHECK FOR VOLTAGE TO THE REVERSING LAMPS RELAY COIL
- Measure the voltage between the reversing lamps relay pin 1, circuit CBB46 (WH/BU), BJB (Battery Junction Box) face side and ground.
Is the voltage greater than 10 volts?
Yes
GO to X4.
No
REPAIR circuit CBB46 (WH/BU) for an open. TEST the system for normal operation.
X4 CHECK THE VOLTAGE SUPPLY CIRCUIT TO THE REVERSING LAMPS RELAY
- Ignition OFF.
- Measure the voltage between the reversing lamps relay pin 3, circuit SBB26 (YE/RD), BJB (Battery Junction Box) face side and ground.
Is the voltage greater than 10 volts?
Yes
GO to X5.
No
VERIFY the BJB (Battery Junction Box) fuse 26 (10A) is OK. If OK, REPAIR circuit SBB26 (YE/RD) for an open. TEST the system for normal operation. If not OK, Refer to the Wiring Diagrams to identify the possible causes of the circuit short. Electrical Diagrams
X5 BYPASS THE REVERSING LAMPS RELAY
- Connect a fused jumper wire between the reversing lamps relay pin 3, circuit SBB26 (YE/RD), BJB (Battery Junction Box) face side and the reversing lamps relay pin 5, circuit CLS10 (GN/BN), BJB (Battery Junction Box) face side.
Do the reversing lamps illuminate?
Yes
REMOVE the jumper wire. GO to X6.
No
REMOVE the jumper wire. REPAIR circuit CLS10 (GN/BN) for an open. TEST the system for normal operation.
X6 CHECK REVERSING LAMPS RELAY COIL CONTROL CIRCUIT FOR A SHORT TO VOLTAGE
- Disconnect: PCM C175T or PCM C1381T.
- Ignition ON.
- Measure the voltage between the reversing lamps relay pin 2, circuit CLS28 (BU/WH), BJB (Battery Junction Box) face side and ground.
Is any voltage present?
Yes
REPAIR circuit CLS28 (BU/WH) for a short to voltage. CLEAR the DTCs. REPEAT the self-test.
No
GO to X7.
X7 CHECK THE REVERSING LAMPS RELAY COIL CONTROL CIRCUIT FOR AN OPEN
- Ignition OFF.
- Connect: Reversing Lamps Relay.
- Ignition ON.
- For vehicles with a 3.7L engine, measure the voltage between the PCM C175T-3, circuit CLS28 (BU/WH), harness side and ground.
- For vehicles with a 3.5L GTDI engine, measure the voltage between the PCM C1381T-33, circuit CLS28 (BU/WH), harness side and ground.
Is the voltage greater than 10 volts?
Yes
GO to X8.
No
REPAIR circuit CLS28 (BU/WH) for an open. CLEAR the DTCs. REPEAT the self-test.
X8 CHECK FOR CORRECT PCM OPERATION
- Disconnect all the PCM connectors.
- Check for:
- corrosion
- damaged pins
- pushed-out pins
- Connect all the PCM connectors and make sure they seat correctly.
- Operate the system and verify the concern is still present.
Is the concern still present?
Yes
INSTALL a new PCM. TEST the system for normal operation.
No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR any DTCs. REPEAT the self-test.