Test Q: The Fog Lamps Are Inoperative

PINPOINT TEST Q: THE FOG LAMPS ARE INOPERATIVE

Q1-Q4:

Q4-Q5:

Q6:

Q7-Q9:

Q9-Q10:

Q10-Q11:

Q11-Q12:

Q13:

Normal Operation
The smart junction box (SJB) sends a voltage signal to the headlamp switch through circuit 1669 (OG/LG). When the fog lamp switch is engaged, the voltage is routed to ground through circuit 1205 (BK). When the SJB detects that the fog lamp switch is engaged, the SJB provides a ground source for the fog lamp relay coil to energize through circuit 1347 (DG/WH). The fog lamp relay receives power from within the bussed electrical center (BEC). When the SJB grounds circuit 1347 (DG/WH), the fog lamp relay switches voltage to circuits 1721 (LB/BK) and 1776 (TN/OG). Circuits 1721 (LB/BK) and 1776 (TN/OG) provide power to the LH and RH fog lamps, respectively. Ground for the fog lamps is supplied by the bussed electrical center (BEC) through circuit 1205 (BK).

Possible Causes
- Fuse
- Circuit 1205 (BK) open
- Circuit 1347 (DG/WH) open or short to voltage
- Circuit 1669 (OG/LG) open
- Circuit 1721 (LB/BK) open
- Circuit 1776 (TN/OG) open
- Fog lamp relay
- Headlamp switch
- BEC
- SJB