DESCRIPTION
Electronic Automatic Temperature Control (EATC) system is a cycling-clutch system that uses a fixed orifice tube to meter the flow of refrigerant. The system includes a self-diagnostic feature that stores fault codes when problems occurs. Some vehicles are equipped with a rear blower motor, located between the front seats, in the center console.
Eatc System Inoperative, Intermittent Or Improper Operation
Go to TEST B .
No Operation In Some Blower Settings
Go to TEST K .
TEST K: NO OPERATION IN SOME BLOWER SETTINGS
- Check Blower Motor Operation Turn ignition to run position (engine off). Press EATC MAX A/C override button. Adjust EATC panel blower speed to midway between high and low. Verify that motor operates. Adjust EATC panel blower speed setting to high. If blower motor speed increases properly with setting changes, system is operating normally. If blower speed does not change properly, go to next step.
- Check Blower Motor Speed Controller Input Voltage Turn ignition off. Disconnect blower motor speed controller connector. Turn ignition to run position (engine off). With a voltmeter, measure voltage between blower motor speed controller connector White/Pink wire and Black wire. If voltage is more than 9 volts, replace blower motor speed controller and retest system. If voltage is less than 9 volts, go to next step.
- Check Blower Motor Speed Controller-To-EATC Connector White/Pink Wire Circuit Disconnect EATC module connector C297. With an ohmmeter, measure White/Pink wire resistance between EATC module connector C297 and blower motor speed controller connector. Then, measure resistance of White/Pink wire between EATC module connector C297 and ground. If resistance is less than 5 ohms between EATC module connector and blower motor speed controller connector White/Pink wire, and more than 10,000 ohms between EATC module connector and ground, replace EATC module and retest system. If resistance is not as specified, repair White/Pink wire and retest system.