Pinpoint Test V: The Reversing Lamps Are Inoperative
Reversing Lamps
Pinpoint Tests
Pinpoint Test V: 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 through circuit CLS28 (BU/WH).
Voltage is supplied from the Battery Junction Box (BJB) fuse 46 (15A) to the coil side of the reversing lamps relay and fuse 26 (20A) to the switched side of the reversing lamps relay. When the reversing lamps relay is energized, voltage is routed to the reversing lamps through circuit CLS10 (GN/BN).
- DTC P1910 (Reverse Lamp Control Circuit/Open) - sets when the PCM detects no voltage on 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 V: 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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V1 CHECK FOR PCM TR SENSOR DTCs FROM THE SELF-TEST
- Review the DTCs from the PCM Key ON Engine OFF (KOEO) self-test.
- Are any TR sensor DTCs present?
Yes
Refer to Transmission Control Systems. Testing and Inspection
No
GO to V2.
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V2 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 V3.
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V3 CHECK FOR VOLTAGE TO THE REVERSING LAMPS RELAY COIL
- Ignition ON.
- 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 V4.
No
VERIFY the BJB fuse 46 (15A) is OK. If OK, REPAIR circuit CBB46 (WH/BU) 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.
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V4 CHECK FOR VOLTAGE TO THE REVERSING LAMPS RELAY SWITCH
- 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 V5.
No
VERIFY the BJB fuse 26 (20A) 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.
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V5 CHECK THE REVERSING LAMPS RELAY OUTPUT FOR AN OPEN
- 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 V7.
No
LEAVE the jumper wire connected. GO to V6.
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V6 CHECK FRO VOLTAGE TO THE BJB FUSE 36 (10A)
- Measure the voltage between the BJB fuse 36 (10A) (output side), circuit CLS10 (GN/BN) and ground.
- Is the voltage greater than 10 volts?
Yes
REMOVE the jumper wire. REPAIR circuit CLS10 (GN/BN) between the fuse and the reversing lamps for an open. TEST the system for normal operation.
No
REMOVE the jumper wire. VERIFY the BJB fuse 36 (10A) is OK. If OK, REPAIR the circuit CLS10 (GN/BN) between the reversing lamps relay and the fuse 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.
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V7 CHECK THE REVERSING LAMPS RELAY COIL GROUND CONTROLLED CIRCUIT FOR A SHORT TO VOLTAGE
- Disconnect: PCM C175t.
- 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. CLEAR the DTCs. REPEAT the self-test.
No
GO to V8.
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V8 CHECK THE REVERSING LAMPS RELAY COIL GROUND CONTROLLED CIRCUIT FOR AN OPEN
- Ignition OFF.
- Connect: Reversing Lamps Relay.
- Ignition ON.
- Measure the voltage between the PCM C175t-3, circuit CLS28 (BU/WH), harness side and ground.
- Is the voltage greater than 10 volts?
Yes
GO to V9.
No
REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
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V9 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.
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