operation abnormality of the license plate light function

1. Operation abnormality of the license plate light function diagnostics

1. Pre-check and visual inspection

1) When the lighting switch is operated, check the illumination status of the license plate light.

Check that the clearance light and taillight illuminate.

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 tail relay.

If a malfunction is found in the relay, replace it.

3) Inspect the lighting switch.

Refer to "9.Body, Cab, Accessories 9A.Lighting Systems combination switch inspection".

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

Refer to "9.Body, Cab, Accessories 9A.Lighting Systems combination switch removal".

Refer to "9.Body, Cab, Accessories 9A.Lighting Systems combination switch installation".

4) Inspect the license plate light bulb.

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

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

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

5) 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 BCM and the license plate light
Between the BCM and the taillight relay
Between the taillight relay and the combination switch

Models without BCM

Between the taillight relay and the license plate light
Between the combination switch and the taillight relay

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".