Test A: The Control Illumination Is Inoperative

PINPOINT TEST A: THE CONTROL ILLUMINATION IS INOPERATIVE

A1-A2:

Normal Operation
The smart junction box (SJB) monitors the input from the instrument panel dimmer switch when the parking lamps are on. The SJB sends a pulse-width modulated (PWM) voltage to the dimmable components based on input received from the instrument panel dimmer switch. The SJB also sends a message over the medium speed controller area network (CAN) to the electronic automatic temperature control (EATC) (if equipped), the audio unit and the instrument cluster to indicate the backlighting intensity level. If the SJB detects a concern with the circuitry to the instrument panel dimmer switch, the SJB defaults the backlighting to a predetermined intensity level.

Possible Causes
- SJB