Symptom Chart

WARNING: This page is about a different car, the 2003 Ford RV Cutaway, 2003 Ford Econoline, 2003 Ford E550 Super Duty, 2003 Ford E450 Super Duty, and 2003 Ford Cutaway. However, it is still accessible from the selected car via links, so may be relevant.

SYMPTOM CHART

Condition	Possible Sources	Action
Incorrect/erratic direction of airflow from outlets	Function selector switch. Vacuum hose/harness. Vacuum control motor. A/C vacuum check valve. Vacuum reservoir tank. Air distribution door/linkage.	GO to PINPOINT TEST A: INCORRECT/ERRATIC DIRECTION OF AIRFLOW FROM OUTLET .
Insufficient, erratic, or no heat	Low engine coolant level. Engine overheating. Plugged or partially plugged heater core. Temperature blend door binding/stuck. Temperature blend door actuator.	GO to PINPOINT TEST B: INSUFFICIENT, ERRATIC, OR NO HEAT .
The air conditioning (A/C) is inoperative/does not operate correctly - 4.6L, 5.4L, 6.8L, and 7.3L engines	Fuse(s). Circuitry open/short. A/C cycling switch. Low refrigerant system charge. Function selector switch. Pressure cutoff switch. A/C compressor clutch air gap. A/C compressor clutch field coil.	GO to PINPOINT TEST C: THE AIR CONDITIONING (A/C) IS INOPERATIVE/DOES NOT OPERATE CORRECTLY - 4.6L, 5.4L, 6.8L, AND 7.3L ENGINES .
The air conditioning (A/C) is inoperative/does not operate correctly - 4.2L engine	Fuse(s). Circuitry open/short. A/C cycling switch. Low refrigerant system charge. Function selector switch. Pressure cutoff switch. A/C control relay. Powertrain control module (PCM). A/C compressor clutch air gap. A/C compressor clutch field coil.	GO to PINPOINT TEST D: THE AIR CONDITIONING (A/C) IS INOPERATIVE/DOES NOT OPERATE CORRECTLY - 4.2L ENGINE .
The air conditioning (A/C) is always on - 4.6L, 5.4L, 6.8L, and 7.3L engines	Circuitry short. Function selector switch. A/C compressor clutch air gap.	GO to PINPOINT TEST E: THE AIR CONDITIONING (A/C) IS ALWAYS ON - 4.6L, 5.4L, 6.8L, AND 7.3L ENGINES .
The air conditioning (A/C) is always on - 4.2L engine	Circuitry short. Function selector switch. A/C control relay. PCM. A/C compressor clutch air gap.	GO to PINPOINT TEST F: THE AIR CONDITIONING (A/C) IS ALWAYS ON - 4.2L ENGINE .
Insufficient air conditioning (A/C) cooling - auxiliary system	Thermostatic expansion valve. Leaking or restricted vacuum hose. Vacuum control motor. Sticking mode door.	GO to PINPOINT TEST G: INSUFFICIENT AIR CONDITIONING (A/C) COOLING - AUXILIARY SYSTEM .
No operation in all the temperature settings	Circuitry open/short. Temperature blend door actuator. Temperature control switch.	GO to PINPOINT TEST H: NO OPERATION IN ALL THE TEMPERATURE SETTINGS .
The blower motor is inoperative	Fuse(s). Circuitry open/short. Blower motor relay. Function selector switch. Blower motor.	GO to PINPOINT TEST I: THE BLOWER MOTOR IS INOPERATIVE .
The blower motor operates continuously in high speed	Blower motor switch. Blower motor resistor. Circuitry short.	GO to PINPOINT TEST J: THE BLOWER MOTOR OPERATES CONTINUOUSLY IN HIGH SPEED .
No operation in high blower setting	Blower motor switch. Circuitry open.	CHECK circuit 261 (OG/BK) for an open between the blower motor C1227 and the blower motor switch C294b. If okay, INSTALL a new blower motor switch.
The auxiliary blower motor is inoperative - vehicles without rear auxiliary blower motor switch	Fuse(s). Circuitry open/short. Auxiliary blower motor relay. Front auxiliary blower motor switch. Auxiliary high speed blower motor relay. Auxiliary blower motor.	GO to PINPOINT TEST K: THE AUXILIARY BLOWER MOTOR IS INOPERATIVE - VEHICLES WITHOUT REAR AUXILIARY BLOWER MOTOR SWITCH .
The auxiliary blower motor is inoperative using the rear auxiliary blower motor switch	Front auxiliary blower motor switch. Rear auxiliary blower motor switch. Circuitry open/short.	GO to PINPOINT TEST L: THE AUXILIARY BLOWER MOTOR IS INOPERATIVE USING THE REAR AUXILIARY BLOWER MOTOR SWITCH .
The front auxiliary blower motor switch operates only in HI	Auxiliary blower motor resistor. Circuitry short. Auxiliary high speed blower motor relay.	GO to PINPOINT TEST M: THE FRONT AUXILIARY BLOWER MOTOR SWITCH OPERATES ONLY IN HI .
The rear auxiliary blower motor switch operates only in HI	Auxiliary blower motor relay. Auxiliary blower motor resistor. Circuitry short.	GO to PINPOINT TEST N: THE REAR AUXILIARY BLOWER MOTOR SWITCH OPERATES ONLY IN HI .
The front auxiliary blower motor switch is inoperative in HI	Fuse(s). Front auxiliary blower motor switch. Circuitry open/short. Auxiliary high speed blower motor relay.	GO to PINPOINT TEST O: THE FRONT AUXILIARY BLOWER MOTOR SWITCH IS INOPERATIVE IN HI .
The rear auxiliary blower motor switch is inoperative in HI	Fuse(s). Rear auxiliary blower motor switch. Circuitry open/short.	CHECK circuit 757 (RD/WH) for an open between S305 and the rear auxiliary blower motor switch C951. If okay, INSTALL a new rear auxiliary blower motor switch.