Symptom Chart

WARNING: This page is about a different car, the 2007 Lincoln MKX and 2007 Ford Edge. 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 (EATC) module	Fuse(s) Circuitry open EATC module communication network	REFER to MODULE COMMUNICATIONS NETWORK .
Air inlet door is inoperative	Circuitry open/shorted EATC module Electronic manual temperature control (EMTC) module Air inlet door actuator/linkage	Go to Pinpoint Test E .
Incorrect/erratic direction of airflow from outlets	Circuitry short/open Door actuator Defrost/panel/floor door actuator/linkage LH or RH blend door actuator/linkage EMTC or EATC module	Go to Pinpoint Test F .
The temperature control is inoperative/does not operate correctly	Circuitry open/shorted Door actuator LH or RH blend door actuator/linkage EMTC or EATC module	Go to Pinpoint Test F .
The EATC system is inoperative, intermittent or incorrect operation	Fuse(s) Circuitry open	Go to Pinpoint Test H .
Insufficient, erratic or no heat	Low engine coolant level Engine overheating Plugged or partially plugged heater core Temperature blend door is binding or stuck Temperature blend door actuator Heater hose is kinked or binding	Go to Pinpoint Test I .
The air conditioning (A/C) is inoperative/does not operate correctly	Open fuse Circuitry short/open PCM EMTC or EATC module A/C compressor A/C control relay A/C evaporator temperature sensor A/C pressure transducer Battery junction box (BJB)	Go to Pinpoint Test J .
The air conditioning (A/C) is always on	Circuitry shorted PCM EMTC or EATC module A/C compressor A/C control relay A/C evaporator temperature sensor A/C pressure transducer	Go to Pinpoint Test K .
The blower motor is inoperative - EMTC	Fuse(s) Circuitry open A/C blower motor switch Blower motor relay A/C blower motor EMTC module	Go to Pinpoint Test L .
The blower motor does not operate correctly - EMTC	Circuitry open/shorted A/C blower motor resistor A/C blower motor switch	Go to Pinpoint Test M .
The blower motor is inoperative - EATC	Fuse(s) Circuitry open/shorted Blower motor relay A/C blower motor EATC module Blower motor speed control	Go to Pinpoint Test N .
The blower motor does not operate correctly - EATC	Circuitry open/shorted Blower motor speed control EATC module A/C blower motor relay	Go to Pinpoint Test O .
The steering wheel control switch is inoperative/does not operate correctly	Circuitry open/shorted Steering wheel control switch EATC module	Go to Pinpoint Test P .
The dual temperature control is inoperative/does not operate correctly	Temperature blend door/actuator broken/binding EATC module Low A/C refrigerant charge	CHECK that the A/C system pressure is above 290 kPa (42 psi). If the pressure is below 290 kPa (42 psi), REFER to Fluorescent Dye Leak Detection . CHECK the temperature blend doors/actuators for a binding or broken condition. If no condition is found, INSTALL a new EATC module.
The temperature set point does not repeat after turning the ignition switch OFF	Open fuse Circuitry short/open EATC module	CHECK circuit SBP15 (WH/RD) for a short or open and repair as necessary. If OK, INSTALL a new EATC module.
The temperature display will not switch between Celsius and Fahrenheit	EATC module Instrument cluster module	If the instrument cluster does not switch between English and Metric, REFER to INSTRUMENT CLUSTER AND PANEL ILLUMINATION . If only the EATC module does not switch between English and Metric, INSTALL a new EATC module.
Inaccurate external temperature display	EATC module Ambient temperature sensor	REFER to Description and Operation of the EATC External Temperature Display. If the external temperature display is not operating as described and no DTC is present, CARRY OUT the Ambient Temperature Sensor . If the sensor tests OK, CARRY OUT the Electronic Automatic Temperature Control (EATC) module and Electronic Manual Temperature Control (EMTC) module cold boot process. If the condition returns, INSTALL a new EATC module. REFER to CLIMATE CONTROL . TEST the system for normal operation.