Test D

PINPOINT TEST D: THE INSTRUMENT CLUSTER ILLUMINATION IS INOPERATIVE

Test D1-D2:

Normal Operation
The headlamp switch supplies the instrument cluster with the headlamp switch position status through circuit 64S-LK29 (BU/RD). The instrument cluster then sends a pulse width modulated (PWM) signal, over the standard corporate protocol (SCP) communication network, to the front electronic module (FEM) which measures the voltage and turns on the intensity of the dimmable backlighting system according to the voltage reading. The instrument cluster is grounded by circuit 31-AL11 (BK).

Possible Causes
- instrument cluster
- circuit 64S-LK29 (BU/RD) open or shorted