Symptom Chart

WARNING: This page is about a different car, the 2003 Ford Windstar. 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 front electronics module (FEM) - unable to carry out the front electronics module (FEM) self-test	Fuse. Low battery voltage. Open ground circuit.	Go To PINPOINT TEST A .
No communication with the rear electronics module (REM) - unable to carry out the rear electronics module (REM) self-test	Fuse. Open ground circuit.	Go To PINPOINT TEST B .
No communication with the hybrid electronic instrument cluster (HEC) - unable to carry out the hybrid electronic instrument cluster (HEC) self-test	Low battery voltage at the HEC. Open HEC ground.	Go To PINPOINT TEST C .
Incorrect/erratic direction of airflow from outlet	Function selector switch. A/C vacuum check valve. Vacuum hose. A/C vacuum reservoir tank and bracket. Vacuum control motor. Vacuum actuator arm.	Go To PINPOINT TEST D .
Insufficient, erratic, or no heat	Low engine coolant level. Engine overheating. Plugged or partially plugged heater core. Temperature blend door binding/stuck. A/C electric blend door actuator.	Go To PINPOINT TEST E .
The A/C does not operate/does not operate correctly	Fuse. Circuitry short/open. A/C cycling switch. A/C system. Function selector switch. A/C refrigerant.	Go To PINPOINT TEST F .
The A/C is always on	Circuitry short/open. A/C cycling switch. A/C control.	Go To PINPOINT TEST G .
No operation in all the temperature settings	Temperature blend door. Temperature blend door actuator control. A/C electronic blend door actuator motor. Circuitry short/open.	Go To PINPOINT TEST H .
The blower motor does not operate/does not operate correctly	Fuse. Circuitry short/open. A/C blower motor switch. A/C blower motor resistor. A/C blower motor.	Go To PINPOINT TEST I .
The blower motor operates continuously in high speed	Circuitry short/open. A/C blower motor resistor. A/C blower motor switch.	Go To PINPOINT TEST J .
No operation in high blower setting	A/C open circuit. A/C blower motor switch.	Go To PINPOINT TEST K .
No operation in low blower setting	A/C open circuit. A/C blower motor resistor. A/C blower motor switch.	Go To PINPOINT TEST L .
The auxiliary blower motor is inoperative	Fuse. Circuitry short/open. Auxiliary blower motor resistor. Auxiliary blower motor.	Go To PINPOINT TEST M .
The auxiliary blower motor does not operate correctly	Fuse. Circuitry short/open. Auxiliary blower motor relay. Auxiliary blower motor speed relay 1. Auxiliary blower motor speed relay 2. Rear auxiliary control. Auxiliary blower motor resistor.	Go To PINPOINT TEST N .
The panel/floor controls do not operate using the front/rear auxiliary controls	Low battery reference voltage. Short to ground. Short to battery. Rear air mode actuator. Rear air temperature door actuator. Rear control module.	Go To PINPOINT TEST O .
The temperature controls do not operate using the front/rear auxiliary climate control	Fuse. Auxiliary air temperature door motor. Auxiliary air temperature door. Short to ground. Short to battery.	Go To PINPOINT TEST P .
The panel/floor and cool/warm controls do not operate using the front/rear auxiliary controls	Circuitry short/open. Auxiliary climate control module.	Go To PINPOINT TEST Q .
The panel/floor and warm/cold control does not operate/does not operate correctly using the rear auxiliary controls	Circuitry short/open. Front/rear auxiliary potentiometer. Auxiliary blend door actuator. Auxiliary climate control module.	Go To PINPOINT TEST R .