F 450 4WD Super Duty V10-6.8L VIN D (2004)
Test AA8-AA9
Tests AB
"Ford service information indicates the Trailer Tow Parking Lamp Relay is within the Central Junction Box (CJB). However, related system testing
and the CJB wiring diagrams do not indicate that the relay is serviceable seperate from the CJB".
PINPOINT TEST AB: THE TRAILER LAMPS ARE INOPERATIVE - TRAILER PARKING LAMPS
Test AB1-AB2