Test U: The Trailer Parking Lamps Are Inoperative

PINPOINT TEST U: THE TRAILER PARKING LAMPS ARE INOPERATIVE

Normal Operation
When the parking lamps are on, the smart junction box (SJB) provides voltage to the trailer tow connector through circuit CAT17 (BN/WH).

This pinpoint test is intended to diagnose the following:
- Fuse
- Wiring, terminals or connectors
- Trailer
- SJB

U1-U3: