Symptom Chart

WARNING: This page is about a different car, the 2007 Ford Pickup, 2007 Ford F550 Super Duty, 2007 Ford F450 Super Duty, and 2007 Ford Cab & Chassis. 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 electronic automatic temperature control module	Fuse(s) Circuitry short/open EATC module communication network	REFER to MODULE COMMUNICATIONS NETWORK article to continue diagnosis of the communication network.
The EATC system is inoperative, intermittent or incorrect operation	Fuse(s) Circuitry short/open Input sensor(s)/erratic input signals Charging system Automatic temperature control sensor hose and elbow	Go to Pinpoint Test E .
Incorrect/erratic direction of air flow from outlets - manual climate control	Fuse(s) Function selector switch Vacuum hose A/C vacuum reservoir tank and check valve Vacuum control motor Vacuum actuator arm	Go to Pinpoint Test F .
Incorrect/erratic direction of air flow from outlets - EATC	EATC module ATC solenoid and manifold assembly Vacuum hose A/C vacuum reservoir tank and check valve Vacuum control motor Vacuum actuator arm	Go to Pinpoint Test G .
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 Incorrect heater control valve operation	Go to Pinpoint Test H .
The air conditioning (A/C) is inoperative/does not operate correctly	Fuse(s) Circuitry short/open A/C cycling switch A/C system discharged/low charge A/C pressure cutoff switch A/C control Function selector switch	Go to Pinpoint Test I .
The air conditioning (A/C) is always on	Circuitry short A/C control A/C compressor clutch air gap	Go to Pinpoint Test J .
Insufficient air conditioning (A/C) cooling	Low refrigerant level Temperature blend door actuator	CARRY OUT the refrigerant system tests. REFER to Refrigerant System Tests .
Temperature control is inoperative/does not operate correctly - manual climate control	Fuse(s) Temperature blend door actuator control Temperature blend door A/C electronic blend door actuator motor Circuitry open/shorted	Go to Pinpoint Test K .
The blower motor is inoperative - manual climate control	Fuse Circuitry open/shorted A/C blower motor switch A/C blower motor resistor Blower motor relay A/C blower motor	Go to Pinpoint Test L .
The blower motor is inoperative - EATC	Circuitry short/open Blower motor relay A/C blower motor A/C blower motor speed control EATC module	Go to Pinpoint Test M .
The blower motor operates continuously in high speed - manual climate control	Circuitry short A/C blower motor switch Blower motor relay	Go to Pinpoint Test N .
No operation in high blower setting - manual climate control	A/C blower motor switch Circuitry short/open	Go to Pinpoint Test O .
No operation in lower speeds - manual climate control	Circuitry short/open A/C blower motor resistor A/C blower motor switch	Go to Pinpoint Test P .
The blower motor does not operate correctly - EATC	Circuitry short/open A/C blower motor speed control A/C blower motor EATC module	Go to Pinpoint Test Q .
The temperature set point does not repeat after turning the ignition switch OFF - EATC	Open fuse Circuitry short/open EATC module	CHECK circuit 22 (LB/BK) for a short or open and repair as necessary. If okay, INSTALL a new EATC module.
The temperature display will not switch between Celsius and Fahrenheit - EATC	EATC module	PRESS the AUTO and DEFROST/FLOOR buttons simultaneously for at least 0.75 second. If the temperature display does not switch between Celsius and Fahrenheit, INSTALL a new EATC module.
The steering wheel control switch is inoperative/does not operate correctly	Circuitry short/open Steering wheel control switch EATC module	Go to Pinpoint Test R .