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Pinpoint Test X: The Reversing Lamps Are Inoperative




Reversing Lamps

Pinpoint Tests

Pinpoint Test X: The Reversing Lamps Are Inoperative

Refer to Wiring Diagram Set 11, Fuse and Relay Information for schematic and connector information. Diagrams By Number

Refer to Wiring Diagram Set 93, Reversing Lamps for schematic and connector information. Diagrams By Number

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 26 (15A) to the switch side of the reversing lamps relay. When the reversing lamps relay is energized, voltage is routed to the reversing lamps.

The PCM relay provides voltage to the reversing lamps relay coil.

- 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
- Liftgate lamp
- 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.

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X1 CHECK THE LIFTGATE PARKING LAMP OPERATION


- Ignition OFF.
- Place the headlamp switch in the PARKING LAMPS ON position.
- Is the liftgate parking lamp illuminated?

Yes
GO to X2.

No
GO to Pinpoint Test R Pinpoint Test R: One Or More Parking, Rear Or License Plate Lamps Is Inoperative.

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X2 CHECK FOR PCM TR SENSOR DTCs FROM THE SELF-TEST


- Place the headlamp switch in the OFF position.
- 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 X3.

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X3 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 X4.

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X4 CHECK FOR VOLTAGE TO THE REVERSING LAMPS RELAY COIL


- Measure the voltage between the reversing lamps relay pin 1, circuit CBB46 (WH/BU), BJB face side and ground.




- Is the voltage greater than 10 volts?

Yes
GO to X5.

No
REPAIR circuit CBB46 (WH/BU) for an open. TEST the system for normal operation.

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X5 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 face side and ground.




- Is the voltage greater than 10 volts?

Yes
GO to X6.

No
VERIFY the BJB fuse 26 (15A) 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. Diagrams By Number

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X6 BYPASS THE REVERSING LAMPS RELAY


- Connect a fused jumper wire between the reversing lamps relay pin 3, circuit SBB26 (YE/RD), BJB face side and the reversing lamps relay pin 5, circuit CLS10 (GN/BN), BJB face side.




- Do the reversing lamps illuminate?

Yes
REMOVE the jumper wire. GO to X8.

No
LEAVE the jumper wire connected. GO to X7.

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X7 CHECK FOR VOLTAGE TO THE LIFTGATE LAMP


- Measure the voltage between the liftgate lamp C4352-2, circuit CLS10 (GN/BN), harness side and ground.




- Is the voltage greater than 10 volts?

Yes
REMOVE the jumper wire. INSTALL a new liftgate lamp assembly. REFER to Rear Lamp Assembly - Liftgate Rear Lamp Assembly - Liftgate. TEST the system for normal operation.

No
REMOVE the jumper wire. REPAIR circuit CLS10 (GN/BN) for an open. TEST the system for normal operation.

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X8 CHECK REVERSING LAMPS RELAY COIL CONTROL CIRCUIT FOR A SHORT TO VOLTAGE


- Disconnect: PCM C175t (3.7L) or C1381t (3.5L GTDI).
- Ignition ON.
- Measure the voltage between the reversing lamps relay pin 2, circuit CLS28 (BU/WH), BJB face side and ground.




- Is any voltage present?

Yes
REPAIR circuit CLS28 (BU/WH) for a short to voltage. TEST the system for normal operation.

No
GO to X9.

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X9 CHECK THE REVERSING LAMPS RELAY COIL CONTROL CIRCUIT FOR AN OPEN


- Ignition OFF.
- Connect: Reversing Lamps Relay.
- Ignition ON.
- For vehicles equipped with a 3.7L engine, measure the voltage between the PCM C175t-3, circuit CLS28 (BU/WH), harness side and ground.




- For vehicles equipped 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 X10.

No
REPAIR circuit CLS28 (BU/WH) for an open. TEST the system for normal operation.

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X10 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. REFER to Computers and Control Systems. 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.

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