Symptom Chart

WARNING: This page is about a different car, the 2005 Mercury Mountaineer and 2005 Ford Explorer. However, it is still accessible from the selected car via links, so may be relevant.

SYMPTOM CHART

Condition	Possible Sources	Action
The horn is inoperative	Circuitry Clockspring Horn switch Horns Horn relay Powertrain control module (PCM)	GO to PINPOINT TEST A .
The horn is always on	Circuitry Clockspring Horn switch Horn relay Vehicle security module Tire pressure monitoring system (TPMS) module	GO to PINPOINT TEST B .