Test A: DTC B1470 - Lamp Headlamp Input Circuit Failure

PINPOINT TEST A: DTC B1470 - LAMP HEADLAMP INPUT CIRCUIT FAILURE

A1:

A1-A2:

Normal Operation
Under normal operation, when the headlamps are turned ON, the headlamp switch sends a ground signal to the smart junction box (SJB) through circuit 1402 (RD/WH). When the headlamps are turned OFF, the headlamp switch sends a ground signal to the SJB through circuit 1400 (TN/YE). When the park lamps are turned ON, the headlamp switch sends a ground signal to the SJB through circuit 1401 (BK/LG).

Possible Causes
- A short to ground in circuit 1400 (TN/YE), 1401 (BK/LG) or 1402 (RD/WH)
- Headlamp switch
- Smart junction box (SJB)