Symptom Chart

WARNING: This page is about a different car, the 2006 Mercury Grand Marquis and 2006 Ford Crown Victoria. However, it is still accessible from the selected car via links, so may be relevant.

SYMPTOM CHART

Condition	Possible Sources	Action
No communication with the instrument cluster	Fuse Circuitry Instrument cluster	GO to PINPOINT TEST A .
Incorrect fuel gauge indication	Circuitry Fuel level sensor Fuel pump module Fuel tank Instrument cluster	GO to PINPOINT TEST B .
Incorrect temperature gauge indication	Powertrain control module (PCM) Instrument cluster	GO to PINPOINT TEST C .
The tachometer is inoperative	Powertrain control module (PCM) Instrument cluster	GO to PINPOINT TEST D .
The speedometer/odometer is inoperative	Fuse Circuitry Powertrain control module (PCM) Instrument cluster	GO to PINPOINT TEST E .
The low fuel warning indicator is never/always on	Fuel pump gauge sender Instrument cluster	GO to PINPOINT TEST F .
The safety belt warning indicator is inoperative (chime is operative)/does not operate correctly	Lighting control module (LCM) Instrument cluster	GO to PINPOINT TEST G .
The check fuel cap warning indicator is never/always on	Powertrain control module (PCM) Instrument cluster	GO to PINPOINT TEST H .
The BRAKE warning indicator is never/always on	Circuitry Parking brake switch Brake fluid level switch Anti-lock brake system (ABS) module Instrument cluster	GO to PINPOINT TEST I .
The charging system warning indicator is never/always on	Charging system Powertrain control module (PCM) Instrument cluster	GO to PINPOINT TEST J .
The fire suppression indicator is never on (police vehicles only)	Circuitry Fire suppression module (FSM) Instrument cluster	GO to PINPOINT TEST K .
The fire suppression indicator is always on (police vehicles only)	Circuitry Fire suppression module (FSM) Instrument cluster	GO to PINPOINT TEST L .
The air suspension indicator is never/always on (if equipped)	Circuitry Air suspension system Air suspension module Instrument cluster	GO to PINPOINT TEST M .
The high beam indicator is never/always on	High beam headlamps Lighting control module (LCM) Instrument cluster	GO to PINPOINT TEST N .
The LH turn indicator is never on	Circuitry LH turn signal lamps Instrument cluster	GO to PINPOINT TEST O .
The RH turn indicator is never on	Circuitry RH turn signal lamps Instrument cluster	GO to PINPOINT TEST P .
The anti-lock brake system (ABS) warning indicator is never/always on	ABS module Instrument cluster	GO to PINPOINT TEST Q .
The traction control indicator is never/always on (if equipped)	Anti-lock brake system (ABS) module Instrument cluster	GO to PINPOINT TEST R .
The low oil pressure warning indicator is never/always on	Circuitry Base engine concern Oil pressure switch Instrument cluster	GO to PINPOINT TEST S .
The malfunction indicator lamp (MIL) indicator is never/always on	Powertrain control module (PCM) Instrument cluster	GO to PINPOINT TEST T .
The air bag indicator warning is never/always on	Circuitry Restraint control module (RCM) Instrument cluster	GO to PINPOINT TEST U .
The speed control indicator is never/always on	Speed control system Powertrain control module (PCM) Instrument cluster	GO to PINPOINT TEST V .
The powertrain malfunction (wrench) warning indicator is never/always on	Powertrain control module (PCM) Instrument cluster	GO to PINPOINT TEST W .
The door/trunk ajar indicator is inoperative (chime is operative)/does not operate correctly	Interior lamps Driver door module (DDM) Instrument cluster	GO to PINPOINT TEST X .
The O/D OFF indicator is never/always on	Transmission O/D off function Powertrain control module (PCM) Instrument cluster	GO to PINPOINT TEST Y .
The engine coolant over temperature warning indicator is never/always on	Powertrain control module (PCM) Instrument cluster	GO to PINPOINT TEST Z .
The engine idle hour meter is inoperative (if equipped)	Instrument cluster	GO to PINPOINT TEST AA .
The instrument cluster is inoperative	Fuse Circuitry Instrument cluster	GO to PINPOINT TEST AB .