Symptom:
*BACKUP LAMPS COME ON WHILE SHIFTER IS NOT IN REVERSE
POSITION
POSSIBLE CAUSES
BACKUP LAMPS ALWAYS ON
BACKUP LAMP SUPPLY CIRCUIT SHORT TO VOLTAGE
INTERMITTENT WIRING AND CONNECTORS
TEST
ACTION
APPLICABILITY
1
Ignition on, engine not running.
Firmly apply brakes.
Place the shift lever in the position which causes the Backup Lamps to come on other
than Reverse.
Do the Backup Lamps come on with the shift lever not in the Reverse position?
All
Yes
→ Go To 2
No
→ Go To 4
2
Ignition on, engine not running.
Place the Shift Lever in the position that causes the Backup Lamps to come on other
than Reverse.
Disconnect the TRS harness connector.
NOTE: This will cause a DTC P0706 and possibly other DTC’s to be stored in
the TCM. They must be erased before returning the vehicle to the customer.
Did the Backup Lamps go out when the TRS harness connector was disconnected?
All
Yes
→ Replace the Transmission Range Sensor per the Service Informa-
tion.
Perform TRANSMISSION NO TROUBLE CODE VERIFICA-
TION TEST.
No
→ Go To 3
3
Turn the ignition off to the lock position.
Disconnect the Transmission TRS harness connector.
NOTE: Check connectors - Clean/repair as necessary.
Ignition on, engine not running.
Measure the voltage of the Back-up Lamp Supply circuit in the TCM harness
connector.
Is the voltage above 0.5 volt?
All
Yes
→ Repair the Backup Lamp Supply circuit for a short to voltage.
Perform TRANSMISSION NO TROUBLE CODE VERIFICA-
TION TEST.
No
→ Test Complete.
425
TRANSMISSION - 42RLE