Test B: The Instrument Cluster Illumination Is Inoperative

PINPOINT TEST B: THE INSTRUMENT CLUSTER ILLUMINATION IS INOPERATIVE

B1-B2:

B2-B4:

Normal Operation

Expedition
The instrument panel dimmer switch generates a variable pulse width modulated (PWM) voltage which is distributed to the instrument cluster on circuit 19 (LB/RD). The instrument cluster is grounded through circuit 57 (BK).

Navigator
The instrument panel dimmer switch generates a pulse width modulated (PWM) voltage which is sent to the instrument cluster on circuit 505 (GY/YE). The instrument cluster is grounded through circuit 676 (PK/OG).

Possible Causes
- circuit 19 (LB/RD) open
- circuit 57 (BK) open
- circuit 505 (GY/YE) open
- circuit 676 (PK/OG) open
- instrument cluster