reverse lights . Automatic transmission or manual .
Principles of Operation
The voltage supply to the reversing lamps is provided by the reversing lamp switch on vehicles equipped with a manual transaxle and by the digital TR sensor on vehicles equipped with an automatic transaxle.
Inspection and Verification
- Verify the customer concern.
- Visually inspect the following for obvious signs of mechanical or electrical damage.
Visual Inspection Chart
Mechanical
Electrical
- Reversing lamp switch (manual transaxle)
- Digital transmission range (TR) sensor (automatic transaxle)
- Central junction box (CJB) fuse(s):
- 40 (10A) (automatic transaxle)
- 53 (10A) (manual transaxle)
- Bulb(s)
- Circuitry
- If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step.
- If the cause is not visually evident, connect the diagnostic tool to the data link connector (DLC) and select the vehicle to be tested from the diagnostic tool menu. If the diagnostic tool does not communicate with the vehicle:
- check that the program card is correctly installed.
- check the connections to the vehicle.
- check the ignition switch position.
- If the diagnostic tool still does not communicate with the vehicle, refer to the diagnostic tool operating manual.
- Carry out the diagnostic tool data link test. If the diagnostic tool responds with:
- ISO circuit fault; all electronic units no communication/not equipped, refer to Section 418-00 .
- No response/not equipped for the GEM, refer to Section 419-10 .
- System passed, retrieve and record the continuous DTCs, erase the continuous DTCs and carry out self-test diagnostics for the GEM.
- If the DTCs retrieved are related to the concern, go to the Generic Electronic Module (GEM) Diagnostic Trouble Code (DTC) Index.
- If no DTCs related to the concern are retrieved, GO to Symptom Chart .
Generic Electronic Module (GEM) Diagnostic Trouble Code (DTC) Index
DTC
Description
Source
Action
B1810
Lamp Back Up Switch Input Circuit Failure
GEM
If the reversing lamps are inoperative, Go To Pinpoint Test Q . If the reversing lamps are always on, Go To Pinpoint Test S .
When the transaxle is placed in REVERSE, voltage is routed to the CJB fuse 40 (10A) through circuit 15S-TA38B (GN/BU). The voltage is then routed to the reversing lamps through circuit 15S-LG9 (GN/BK).
Possible Causes
- Fuse
- Circuit 15-LG28 (GN/WH) open
- Circuit 15S-LG3 (GN/YE) open
- Circuit 15S-TA38B (GN/BU) open
- Circuit 15S-LG9 (GN/BK) open
- Reversing lamp switch
- CJB
PINPOINT TEST Q: THE REVERSING LAMPS ARE INOPERATIVE
Test Step
Result / Action to Take
Q1 DETERMINE THE TRANSAXLE TYPE
- Check the vehicle and determine the type of transaxle.
- Is the vehicle equipped with a manual transaxle?
Yes
GO to Q2 .
No
GO to Q5 .
Q2 CHECK THE VOLTAGE TO THE REVERSING LAMP SWITCH
- Key in OFF position.
- Disconnect: Reversing Lamp Switch C1407.
- Key in ON position.
- Measure the voltage between the reversing lamp switch C1407-2, circuit 15-LG28 (GN/WH), harness side and ground.
- Is the voltage greater than 10 volts?
Yes
GO to Q4 .
No
VERIFY the CJB fuse 53 (10A) is OK. If OK, GO to Q3 .
Q3 CHECK CIRCUIT 15-LG28 (GN/WH) FOR AN OPEN
- Key in OFF position.
- Disconnect: CJB C270f.
- Measure the resistance between the reversing lamp switch C1407-2, circuit 15-LG28 (GN/WH), harness side and the CJB C270f-9, circuit 15-LG28 (GN/WH), harness side.
- Is the resistance less than 5 ohms?
Yes
INSTALL a new CJB. TEST the system for normal operation.
No
REPAIR the circuit. TEST the system for normal operation.
Q4 CHECK CIRCUIT 15S-LG3 (GN/YE) FOR AN OPEN
- Key in OFF position.
- Connect a fused (10A) jumper wire between the reversing lamp switch C1407-2, circuit 15-LG28 (GN/WH), harness side and the reversing lamp switch C1407-1, circuit 15S-LG3 (GN/YE), harness side.
- Key in ON position.
- Do the reversing lamps illuminate?
Yes
INSTALL a new reversing lamp switch. REFER to Reversing Lamp Switch in this section. TEST the system for normal operation.
No
REPAIR the circuit. TEST the system for normal operation.
Q5 CHECK THE PCM TRANSMISSION PIDs
- Key in ON position.
- Enter the following diagnostic mode on the diagnostic tool: PCM Transmission Range PID.
- Monitor the PCM transmission range PID while moving the transmission shift lever through all the transmission ranges.
- Do the transmission ranges agree with the PIDs?
Yes
GO to Q6 .
No
REFER to Section 307-01 to continue diagnosis of the transmission.
Q6 CHECK CIRCUIT 15S-TA38B (GN/BU) FOR AN OPEN
- Key in OFF position.
- Disconnect: CJB C270d.
- Apply the parking brake.
- Key in ON position.
- Place the transmission in REVERSE.
- Measure the voltage between the CJB C270d-14, circuit 15S-TA38B (GN/BU), harness side and ground.
- Is the voltage greater than 10 volts?
Yes
PLACE the transmission in PARK. GO to Q7 .
No
REPAIR the circuit. TEST the system for normal operation.
Q7 CHECK CIRCUIT 15S-LG9 (GN/BK) FOR AN OPEN
- Key in OFF position.
- Connect a fused (10A) jumper wire between the CJB C270d-14, circuit 15S-TA38B (GN/BU), harness side and the CJB C270d-15, circuit 15S-LG9 (GN/BK), harness side.
- Key in ON position.
- Place the transmission in REVERSE.
- Do the reversing lamps illuminate?
Yes
INSTALL a new CJB. TEST the system for normal operation.
No
REPAIR the circuit. TEST the system for normal operation.