Pinpoint Test T: The Reversing Lamps Are On Continuously
Reversing Lamps
Pinpoint Test T: The Reversing Lamps Are On Continuously
Refer to Wiring Diagram Set 93, Reversing Lamps for schematic and connector information. Diagrams By Number
Normal Operation
The reversing lamps are illuminated, voltage is also provided to the Body Control Module (BCM), the auto-dimming interior rear view mirror and the Global Positioning System Module (GPSM) if equipped.
Automatic Transaxle
The reversing lamps are provided voltage from the reversing lamps relay. Voltage is supplied to the reversing lamps relay when the ignition is in RUN. The Transmission Control Module (TCM) monitors the transaxle gear status. When the TCM detects the transaxle is in REVERSE (R), the TCM provides a ground for the reversing lamps relay coil. When the relay is energized, voltage is supplied to the reversing lamps.
Manual Transaxle
Voltage is supplied to the reversing lamp switch when the ignition is in RUN. When the transaxle is in REVERSE (R), the reversing lamp switch routes voltage to the reversing lamps.
- DTC C1137:24 (Reverse Gear Switch: Signal Stuck High) - A continuous and on-demand DTC that sets when the BCM detects a short to voltage from the reversing lamp voltage supply circuit.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Reversing lamps relay (automatic transaxle)
- Reversing lamp switch (manual transaxle)
- Auto-dimming interior rear view mirror
- BCM
- GPSM
- TCM (automatic transaxle)
PINPOINT TEST T: THE REVERSING LAMPS ARE ON CONTINUOUSLY
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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T1 DETERMINE THE TRANSAXLE TYPE
- Ignition OFF.
- Check the vehicle for a manual transaxle.
- Is the vehicle equipped with a manual transaxle?
Yes
GO to T2.
No
GO to T3.
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T2 CHECK THE REVERSING LAMP SWITCH
- Ignition OFF.
- Disconnect: Reversing Lamp Switch C169.
- Ignition ON.
- Do the reversing lamps continue to illuminate?
Yes
If equipped with a GPSM, GO to T4. If not equipped with a GPSM, GO to T5.
No
INSTALL a new reversing lamp switch. REFER to Reversing Lamp Switch Service and Repair. TEST the system for normal operation.
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T3 CHECK THE REVERSING LAMPS RELAY OUTPUT
- Ignition OFF.
- Disconnect: Reversing Lamps Relay.
- Ignition ON.
- Do the reversing lamps continue to illuminate?
Yes
If equipped with a GPSM, GO to T4. If not equipped with a GPSM, GO to T5.
No
GO to T7.
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T4 CHECK THE GPSM FOR A SHORT TO VOLTAGE
- Ignition OFF.
- Disconnect: GPSM C2398.
- Ignition ON.
- Do the reversing lamps continue to illuminate?
Yes
GO to T5.
No
GO to T10.
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T5 CHECK THE BCM FOR A SHORT TO VOLTAGE
- Ignition OFF.
- Disconnect: BCM C2280D.
- Ignition ON.
- Do the reversing lamps continue to illuminate?
Yes
If equipped with an auto-dimming interior rear view mirror, GO to T6. If not equipped with an auto-dimming interior rear view mirror, REPAIR circuit CET47 (BU) for a short to voltage. TEST the system for normal operation.
No
GO to T11.
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T6 CHECK THE AUTO-DIMMING INTERIOR REAR VIEW MIRROR FOR A SHORT TO VOLTAGE
- Ignition OFF.
- Disconnect: Auto-Dimming Interior Rear View Mirror C911.
- Ignition ON.
- Do the reversing lamps continue to illuminate?
Yes
REPAIR circuit CET47 (BU) for a short to voltage. TEST the system for normal operation.
No
INSTALL a new auto-dimming interior rear view mirror. REFER to Rear View Mirrors Interior Rear View Mirror. TEST the system for normal operation.
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T7 CHECK THE REVERSING LAMPS RELAY
- Ignition OFF.
- Substitute a known good relay.
- Ignition ON.
- Do the reversing lamps continue to illuminate?
Yes
REMOVE the known good relay. GO to T8.
No
REMOVE the known good relay. INSTALL a new reversing lamps relay. TEST the system for normal operation.
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T8 CHECK THE REVERSING LAMPS RELAY COIL GROUND CONTROLLED CIRCUIT FOR A SHORT TO GROUND
- Ignition OFF.
- Connect: Reversing Lamps Relay.
- Disconnect: TCM C1750A.
- Ignition ON.
- Do the reversing lamps continue to illuminate?
Yes
REPAIR circuit CLS28 (BU/WH) for a short to ground. TEST the system for normal operation.
No
GO to T9.
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T9 CHECK THE TCM GEAR STATUS INPUT PID
- Ignition OFF.
- Connect: TCM C1750A.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: TCM DataLogger.
- Monitor the TCM gear status PID (GEAR_ENGAGED) while placing the gear selector lever through all its positions.
- Does the PID agree with the gear selections?
Yes
GO to T12.
No
REFER to Automatic Shifting Manual Transmission/Transaxle Testing and Inspection to continue diagnosis of the gear input.
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T10 CHECK FOR CORRECT GPSM OPERATION
- Ignition OFF.
- Disconnect all the GPSM connectors.
- Check for:
- corrosion
- damaged pins
- pushed-out pins
- Connect all the GPSM 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 GPSM. REFER to Information and Entertainment Systems Service and Repair. 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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T11 CHECK FOR CORRECT BCM OPERATION
- Ignition OFF.
- Disconnect all the BCM connectors.
- Check for:
- corrosion
- damaged pins
- pushed-out pins
- Connect all the BCM 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 BCM. REFER to Multifunction Electronic Modules Body Control Module (BCM). 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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T12 CHECK FOR CORRECT TCM OPERATION
- Ignition OFF.
- Disconnect all the TCM connectors.
- Check for:
- corrosion
- damaged pins
- pushed-out pins
- Connect all the TCM 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 TCM. REFER to Automatic Shifting Manual Transmission/Transaxle Transmission Control Module (TCM). 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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