Test A: The Control Illumination Is Inoperative - All Hardwired Illumination

PINPOINT TEST A: THE CONTROL ILLUMINATION IS INOPERATIVE - ALL HARDWIRED ILLUMINATION

Normal Operation
When the headlamp switch is placed in the PARKING or HEADLAMP ON position, the smart junction box (SJB) supplies either a pulse width modulated (PWM) signal or 12 volts to the various backlighting sources in the instrument panel, doors and console.

- DTC B2027 (LED Backlighting Output Circuit Failure) - is a continuous and on-demand DTC that sets when the SJB detects a short to ground on the dimmable backlighting circuits.

This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- SJB

A1-A3:

A3-A4: