Econoline E350 1 Ton V8-5.4L CNG VIN M (1999)
Trailer Lamps: Initial Inspection and Diagnostic Overview
1. Check the trailer feed wiring and the added trailer connector for obvious signs of damage.
2. Check the fuses and relays for damage.
3. If the concern remains after the inspection, determine the symptom(s) and proceed to the Symptom Chart. See: Symptom Related Diagnostic
Procedures