Symptom Chart

WARNING: This page is about a different car, the 2006 Mercury Milan, 2006 Lincoln Zephyr, and 2006 Ford Fusion. 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 anti-lock brake system (ABS) module	Smart junction box (SJB) fuse 28 (10A) Circuitry ABS module	GO to PINPOINT TEST A .
No communication with the instrument cluster	Circuitry Instrument cluster	REFER to INSTRUMENT CLUSTER to continue diagnosis of the instrument cluster.
The red brake warning indicator does not self-check	Instrument cluster	REFER to INSTRUMENT CLUSTER .
The red brake warning indicator stays on when the ignition switch is in RUN	Circuitry Low brake fluid warning switch Parking brake switch Instrument cluster	REFER to INSTRUMENT CLUSTER .
The yellow ABS warning indicator is always on	Circuitry Instrument cluster ABS module	GO to PINPOINT TEST G .
Spongy brake pedal with no warning indicator	Air in the brake hydraulic system	GO to PINPOINT TEST H .
Poor vehicle tracking during anti-lock function	Air in the hydraulic brake system Hydraulic control unit (HCU)	GO to PINPOINT TEST I .
Poor vehicle tracking during anti-lock function	Base brake system	REFER to BRAKE SYSTEM-GENERAL INFORMATION .
False ABS activation with no DTCs present	Incorrect or worn tires Underinflated tire(s) Non-OEM suspension components Missing, damaged or misaligned wheel speed sensor tone rings	INSPECT the wheels and tires, front and rear suspension and the wheel speed sensor tone rings. REPAIR or INSTALL new as necessary.
The traction control system is inoperative	Traction control system is turned off	MAKE SURE the system is turned on. CARRY OUT the ABS module self-test. CHECK for DTCs. REFER to ANTI-LOCK BRAKE SYSTEM (ABS) MODULE DIAGNOSTIC TROUBLE CODE (DTC) CHART .
	Traction control system is not configured	CHECK the PCM configuration. REFER to MODULE CONFIGURATION .
	ABS wheel speed sensor fault	CARRY OUT the ABS module self-test. CHECK for DTCs. REFER to ANTI-LOCK BRAKE SYSTEM (ABS) MODULE DIAGNOSTIC TROUBLE CODE (DTC) CHART .
	CAN communications bus fault	CHECK for DTCs. REFER to MODULE COMMUNICATIONS NETWORK .
The traction control warning indicator is always on	Traction control system is turned off	MAKE SURE the system is turned on. CARRY OUT the ABS module self-test. CHECK for DTCs. REFER to ANTI-LOCK BRAKE SYSTEM (ABS) MODULE DIAGNOSTIC TROUBLE CODE (DTC) CHART .
	Traction control system is not configured	CHECK the PCM configuration. REFER to MODULE CONFIGURATION .
	ABS wheel speed sensor fault	CARRY OUT the ABS module self-test. CHECK for DTCs. REFER to ANTI-LOCK BRAKE SYSTEM (ABS) MODULE DIAGNOSTIC TROUBLE CODE (DTC) CHART .
	Instrument cluster	GO to PINPOINT TEST J .
The traction control system cannot be disabled/enabled	Circuitry Traction control switch Instrument cluster	GO to PINPOINT TEST J .