Test U
PINPOINT TEST U: THE FOG LAMPS ARE ON CONTINUOUSLYTest U1-U2:
Test U3:
Normal Operation
The fog lamps receive power from the fog lamp relay (when energized) through circuit 478 (TN/OG). When the fog lamp switch (integral to the headlamp switch) is engaged, power is switched to circuit 477 (LB/BK) which flows to the fog lamp relay coil. When the fog lamp relay is energized, the relay allows power from circuit 462 (VT) to flow through to circuit 478 (TN/OG) to the fog lamps.
Possible Causes
- circuit 477 (LB/BK) short to power
- circuit 478 (TN/OG) short to power
- headlamp switch
- fog lamp relay