Test A: The Control Illumination Is Inoperative

PINPOINT TEST A: THE CONTROL ILLUMINATION IS INOPERATIVE

A1-A4:

A4-A6:

A7:

Normal Operation
When the headlamp switch is in the park or headlamp ON position a voltage signal is sent to the smart junction box (SJB) through circuit 14 (BN). Voltage is supplied from the SJB to the instrument panel dimmer switch on circuit 19 (LB/RD). The instrument panel dimmer switch generates a variable pulse width modulated (PWM) signal that is distributed to the dimmable components and switches through circuit 1045 (DB/WH). The instrument panel dimmer switch is grounded through circuit 57 (BK).

Possible Causes
- fuse
- circuit 14 (BN) open
- circuit 19 (LB/RD) open or short to ground
- circuit 57 (BK) open
- circuit 1045 (DB/WH) open or short to ground
- headlamp switch
- smart junction box (SJB)