Operation abnormality of the backup light function

1. Operation abnormality of the backup light function diagnostics

1. Pre-check and visual inspection

1) Verify that the back buzzer sounds.

2) Check for any interference from aftermarket electronic components such as two-way radios or lights.

Turn OFF or remove any aftermarket electronic components to ensure that there is no influence on inspections or operations.

2. Components inspection

1) Inspect the fuse.

If an abnormal condition such as a fuse blowout is found, inspect or repair the cause of the abnormal condition before replacing the fuse.

2) Inspect the backup light switch.

If a malfunction is found in the backup light switch, replace it.

3) Inspect the backup light bulb.

If any abnormal conditions are found in the backup light bulb, replace it.

Refer to "9.Body, Cab, Accessories 9A.Lighting Systems backup light bulb removal".

Refer to "9.Body, Cab, Accessories 9A.Lighting Systems backup light bulb installation".

4) Inspect the BCM.

Observe the DTC information, and replace the BCM if a malfunction is found.

Caution

  • Perform programming after replacing the BCM.

Refer to "9.Body, Cab, Accessories 9Z.Body, Cab, Accessories Electrical Control BCM removal".

Refer to "9.Body, Cab, Accessories 9Z.Body, Cab, Accessories Electrical Control BCM installation".

Refer to "9.Body, Cab, Accessories 9Z.Body, Cab, Accessories Electrical Control BCM setting".

3. Circuit inspection

1) Check that the ground point is normal.

Repair or clean any ground points that are improperly installed or significantly dirty.

2) Check that the harnesses and connectors are normal.

Inspect for the following circuits for an open circuit, short, poor connections at the connectors, and abnormal conditions such as worn or bent harnesses.

Models with BCM

  • Between the fuse and the backup light switch
  • Between the backup light switch and the BCM
  • Between the BCM and the rear combination light

Models without BCM

  • Between the fuse and the backup light switch
  • Between the backup light switch and the rear combination light

Caution

  • When checking the continuity between the harnesses, disconnect the battery negative terminal.

Refer to "201.General Information 14A.Service Information Guide Preliminary and post procedures".