Diesel Data: Automotive Repair

Test X: The Fog Lamps ON Indicator Is Inoperative

PINPOINT TEST X: THE FOG LAMPS ON INDICATOR IS INOPERATIVE


X1-X3:






X4:






Normal Operation
Under normal operation, when fog lamps are selected, the smart junction box (SJB) sends voltage to the fog lamp ON indicator in the headlamp switch through circuit 1407 (LB/OG).

Possible Causes
- An open in circuit 1407 (LB/OG)
- A short to ground in circuit 1407 (LB/OG)
- Headlamp switch
- Smart junction box (SJB)