Symptom Chart

WARNING: This page is about a different car, the 2003 Mercury Mountaineer and 2003 Ford Explorer. However, it is still accessible from the selected car via links, so may be relevant.

SYMPTOM CHART

Condition	Possible Sources	Action
The steering wheel control switch is inoperative/does not operate correctly	Circuitry short/open. Steering wheel control switch. DATC module.	Go To PINPOINT TEST E .
No communication with the dual electronic automatic temperature control (DATC) module	Circuitry short/open. DATC module communication network.	Go To PINPOINT TEST F .
The DATC system is inoperative, intermittent or incorrect operation	Circuitry short/open. Input sensor(s)/erratic input signals. Automatic temperature control aspirator hose and elbow.	Go To PINPOINT TEST G .
Incorrect/erratic direction of airflow from outlets - manual climate control	Function selector switch. Vacuum hose. A/C vacuum reservoir tank and check valve. Vacuum control motor. Vacuum actuator arm. Mode door.	Go To PINPOINT TEST H .
Incorrect/erratic direction of airflow from outlets - DATC	DATC module. ATC solenoid and manifold assembly. Vacuum hose. A/C vacuum reservoir tank and check valve. Vacuum control motor. Vacuum actuator arm. Mode door.	Go To PINPOINT TEST I .
Insufficient, erratic, or no heat	Low engine coolant level. Engine overheating. Plugged or partially plugged heater core. Temperature blend door is binding or stuck. A/C electric blend door actuator. Incorrect heater control valve operation. Heater hose is kinked or binding.	Go To PINPOINT TEST J .
The A/C is inoperative/does not operate correctly	Open fuse. Circuitry short/open. A/C system discharged/low charge. A/C pressure cutoff switch. A/C control. Function selector switch. A/C cycling switch. A/C compressor clutch air gap. A/C clutch relay.	Go To PINPOINT TEST K .
The A/C is always on	Circuitry short. A/C control. A/C compressor clutch air gap. A/C clutch relay.	Go To PINPOINT TEST L .
The temperature control is inoperative/does not operate correctly - manual climate control	Temperature blend door actuator control. Temperature blend door. A/C electronic blend door actuator motor. Circuitry open/shorted.	Go To PINPOINT TEST M .
The blower motor is inoperative - manual climate control	Fuse. Circuitry open/shorted. A/C blower motor switch. Blower motor relay. A/C blower motor.	Go To PINPOINT TEST N .
The blower motor does not operate correctly - manual climate control	Circuitry short. A/C blower motor resistor. A/C blower motor switch. Blower motor high speed relay.	Go To PINPOINT TEST O .
The blower motor is inoperative - DATC	Circuitry short/open. Blower motor relay. A/C blower motor. A/C blower motor speed control.	Go To PINPOINT TEST P .
The blower motor does not operate correctly - DATC	Circuitry short/open. A/C blower motor speed control. DATC module.	Go To PINPOINT TEST Q .
The auxiliary blower motor is inoperative	Fuse. Circuitry short/open. Auxiliary blower motor relay. Auxiliary blower motor.	Go To PINPOINT TEST R .
The auxiliary blower motor does not operate correctly using the front auxiliary climate controls	Fuse. Circuitry short/open. Auxiliary blower motor switch. Auxiliary blower motor resistor.	Go To PINPOINT TEST S .
The auxiliary blower motor does not operate correctly using the rear auxiliary climate controls	Fuse. Circuitry short/open. Auxiliary blower motor switch. Auxiliary blower motor resistor.	Go To PINPOINT TEST T .
The panel/floor control is inoperative using the front auxiliary climate controls	Fuse. Circuitry short/open. Front auxiliary control panel. Auxiliary mode door actuator. Mode door.	Go To PINPOINT TEST U .
The panel/floor control is inoperative using the rear auxiliary climate controls	Fuse. Circuitry short/open. Rear auxiliary control panel. Front auxiliary control panel.	Go To PINPOINT TEST V .
The temperature control is inoperative using the front auxiliary climate controls	Fuse. Circuitry short/open. Front auxiliary control panel. Auxiliary blend door actuator. Temperature blend door.	Go To PINPOINT TEST W .
The temperature control is inoperative using the rear auxiliary climate controls	Fuse. Circuitry short/open. Rear auxiliary control panel. Front auxiliary control panel.	Go To PINPOINT TEST X .
The panel/floor and cool/warm controls are inoperative using the front auxiliary climate controls	Fuse. Circuitry short/open. Auxiliary blower motor switch. Front auxiliary control panel.	Go To PINPOINT TEST Y .
The panel/floor and cool/warm controls are inoperative using the rear auxiliary climate controls	Fuse. Circuitry short/open. Auxiliary blower motor switch. Rear auxiliary control panel. Front auxiliary control panel.	Go To PINPOINT TEST Z .
Insufficient air conditioning (A/C) cooling	Low refrigerant level. A/C cycling switch. Temperature blend door actuator control. A/C pressure cutoff switch. Heater control valve. Vacuum line blocked or leaking.	Go To PINPOINT TEST AA .
The dual temperature control is inoperative/does not operate correctly	Temperature blend door/actuator broken/binding. DATC module.	CHECK the temperature blend doors/actuators for a binding or broken condition. If no condition is found, Go To PINPOINT TEST A . If the LH temperature control is not correct diagnose for DTC B2266. If the RH temperature control is not correct diagnose for DTC B2267.
The temperature set point does not repeat after turning the ignition switch OFF	Open fuse. Circuitry short/open. DATC module.	CHECK circuit 729 (RD/WH) for a short or open and repair as necessary. If okay, INSTALL a new DATC module. REFER to CLIMATE CONTROL ASSEMBLY - DATC .
The temperature display will not switch between Celsius and Fahrenheit	DATC module.	INSTALL a new DATC module. REFER to CLIMATE CONTROL ASSEMBLY - DATC .