Symptom Chart

WARNING: This page is about a different car, the 2004 Mercury Mountaineer and 2004 Ford Explorer. However, it is still accessible from the selected car via links, so may be relevant.

SYMPTOM CHART

Condition	Possible Sources	Action
The trailer lamps are inoperative	Circuitry. Trailer.	Go To PINPOINT TEST Y .
The trailer lamps are inoperative - RH trailer turn/stoplamp	Circuitry. Trailer tow RH turn relay. Trailer.	Go To PINPOINT TEST Z .
The trailer lamps are inoperative - LH trailer turn/stoplamp	Circuitry. Trailer tow LH turn relay. Trailer.	Go To PINPOINT TEST AA .
The trailer lamps are inoperative - parking lamps	Circuitry. Trailer parking lamp relay. Trailer.	Go To PINPOINT TEST AB .
The trailer lamps are inoperative - reversing lamps	Circuitry. Trailer reversing lamp relay. Trailer.	Go To PINPOINT TEST AC .
The trailer lamps are on continuously	Circuitry. Trailer tow relay. Trailer.	Go To PINPOINT TEST AD .
The trailer battery charging is inoperative	Circuitry. Trailer battery charge relay. Trailer.	Go To PINPOINT TEST AF .
The trailer electric brakes are inoperative	Circuitry. Trailer electronic brake control module Trailer.	Go To PINPOINT TEST AF .