Symptom Chart

WARNING: This page is about a different car, the 2003 Mercury Marauder, 2003 Mercury Grand Marquis, and 2003 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 lighting control module	Central junction box (CJB) fuse(s): 21 (15A). 15 (15A). 23 (15A). 6 (15A). 27 (25A). Lighting control module (LCM). Circuitry.	REFER to MULTIFUNCTION ELECTRONIC MODULE .
Incorrect fuel gauge indication	Central junction box (CJB) fuse 6 (15A). Circuitry. Fuel gauge. Fuel tank. Fuel indicator module. Instrument cluster printed circuit. Fuel sender.	Go To PINPOINT TEST A .
Incorrect temperature gauge indication	Central junction box (CJB) fuse 13 (15A). Circuitry. Engine coolant temperature sender. Engine coolant temperature gauge. Instrument cluster printed circuit.	Go To PINPOINT TEST B .
Incorrect oil pressure gauge indication (except Marauder)	Central junction box (CJB) fuse 13 (15A). Circuitry. Engine oil pressure switch. Engine oil pressure gauge. Instrument cluster printed circuit.	For all vehicles except the Marauder, Go To PINPOINT TEST C . For the Marauder, REFER to WARNING DEVICES .
Incorrect voltage gauge indication (except Marauder)	Instrument cluster printed circuit. Voltage gauge (part of the fuel gauge).	For all vehicles except the Marauder, INSTALL a new voltage gauge (part of the fuel gauge). TEST the system for normal operation. For the Marauder, REFER to WARNING DEVICES .
The speedometer/odometer is inoperative	Battery junction box (BJB) fuse 114 (30A). Central junction box (CJB) fuse 6 (15A). Vehicle speed sensor (VSS). Circuitry. Speedometer/odometer. Instrument cluster printed circuit.	Go To PINPOINT TEST D .
The tachometer is inoperative (Marauder only)	Circuitry. Tachometer gauge. Instrument cluster printed circuit.	Go To PINPOINT TEST E .
The low fuel warning indicator is never/always on	Fuel gauge and fuel indicator module. Instrument cluster printed circuit.	Go To PINPOINT TEST F .
The charge system warning indicator is never on	Central junction box (CJB) fuse 14 (10A). Circuitry. Powertrain control module (PCM). Instrument cluster printed circuit.	Go To PINPOINT TEST G .
The charging system warning indicator is always on	Circuitry. Generator. Powertrain control module (PCM). Instrument cluster printed circuit.	REFER to GENERATORS & REGULATORS .
The brake warning indicator is always on	Circuitry. Park brake switch. Brake fluid level switch. Bulb check relay. Ignition switch.	REFER to BRAKE SYSTEM-GENERAL INFORMATION .
The brake warning indicator is never on	Circuitry. Brake warning indicator miniature bulb. Park brake switch. Brake check relay. Brake fluid level switch. Instrument cluster printed circuit. Ignition switch.	Go To PINPOINT TEST H .
The CHECK ENGINE indicator is always on	Circuitry. CHECK ENGINE warning indicator miniature bulb. Powertrain control module (PCM). Instrument cluster printed circuit.	REFER to SELF-DIAGNOSTICS - CNG, FLEX-FUEL & GASOLINE .
The CHECK ENGINE indicator is never on	Circuitry. CHECK ENGINE (MIL) warning indicator miniature bulb. Powertrain control module (PCM). Instrument cluster.	Go To PINPOINT TEST I .
The safety belt warning indicator is inoperative (chime is operative)	Circuitry. Safety belt buckle switch. Safety belt indicator miniature bulb. Lighting control module (LCM). Instrument cluster printed circuit.	Go To PINPOINT TEST J .
The air suspension indicator is never/always on	Circuitry. Battery junction box (BJB) fuse 114 (30A). Air suspension module. Air suspension indicator miniature bulb. Instrument cluster printed circuit.	Go To PINPOINT TEST K .
The LH turn indicator is never on	Circuitry. LH turn indicator miniature bulb. Instrument cluster printed circuit.	Go To PINPOINT TEST L .
The RH turn indicator is never on	Circuitry. RH turn indicator miniature bulb. Instrument cluster printed circuit.	Go To PINPOINT TEST M .
The high beam indicator is never on	Circuitry. High beam indicator miniature bulb. Instrument cluster printed circuit. Multifunction switch.	Go To PINPOINT TEST N .
The traction control indicator is never/always on	Indicator lamp module. Anti-lock brake system/traction control (ABS/TC) module. Circuitry.	Go To PINPOINT TEST O .
The O/D OFF indicator is never on	Circuitry. Overdrive off indicator miniature bulb. Powertrain control module (PCM). Instrument cluster printed circuit.	Go To PINPOINT TEST P .
The anti-lock brake system (ABS) warning indicator is always on	Circuitry. Instrument cluster printed circuit. Anti-lock brake system/traction control (ABS/TC) module.	REFER to ANTI-LOCK CONTROL-TRACTION CONTROL .
The anti-lock brake system (ABS) warning indicator is never on	Circuitry. ABS indicator miniature bulb. Anti-lock brake system/traction control (ABS/TC) module. Instrument cluster printed circuit.	Go To PINPOINT TEST Q .
The fail-safe cooling warning indicator is never on	Circuitry. Fail-safe cooling indicator miniature bulb. Engine coolant temperature sender. Powertrain control module (PCM). Instrument cluster printed circuit.	Go To PINPOINT TEST R .
The CHECK FUEL CAP indicator is never/always on	Circuitry. Fuel evaporative system. Powertrain control module (PCM). Instrument cluster.	Go To PINPOINT TEST S .
The AIR BAG warning indicator is never on	Circuitry. Indicator lamp module. Restraint control module (RCM). Air bag indicator miniature bulb.	Go To PINPOINT TEST T .
The AIR BAG warning indicator is always on	Circuitry. Indicator lamp module. Restraint control module (RCM).	REFER to AIR BAG RESTRAINT SYSTEMS .
The instrument cluster is inoperative	Central junction box (CJB) fuse(s): 6 (15A). 14 (10A). Battery junction box (BJB) fuse 114 (30A). Circuitry. Instrument Cluster printed circuit.	Go To PINPOINT TEST U .