FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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Electronic Climate Control

1. Verify the customer's concern by operating the electronic automatic temperature control to duplicate the condition.
2. Inspect to determine if one of the following mechanical or electrical concerns apply:

VISUAL INSPECTION CHART

Mechanical
- Vacuum hose damaged.
- A/C system damaged.
- Damaged drive belt.
- Clogged passenger compartment air filter.

Electrical
- Open fuse(s).
- Circuitry misrouted/damaged.
- Connectors damaged/disconnected.

3. If inspection reveals an obvious concern that is readily serviced, correct the concern before continuing with Inspection and Verification.
4. If the concern remains after the inspection, use the Rotunda New Generation Star (NGS) Tester 418-F048 (007-00500) or equivalent connected to the Data Link Connector (DLC) located beneath the instrument panel and select the vehicle to be tested from the NGS tester menu. If the vehicle selection cannot be entered:
- check that program card is properly installed.
- check connections to vehicle.
- check ignition switch position.

If the NGS tester still does not allow the vehicle selection to be entered, refer to the New Generation Star (NGS) Tester manual.
5. Perform DATA LINK DIAGNOSTIC TEST using the NGS tester. If the NGS tester responds with:
- CKT 914, CKT 915 or CKT 70=ALL MODULES NO RESPONSE/NOT EQUIPPED, go to Information Bus to diagnose network concern.
- If the Remote Climate Control (RCC) module is not listed for a communication concern, execute self-test diagnostics for the Remote Climate Control (RCC) module.
- If the Powertrain Control Module (PCM) is not listed for a communication concern, turn the electronic automatic temperature control system OFF and execute self-test diagnostics for the PCM.
6. If the EATC or PCM DTCs retrieved are related to the concern, go to the Electronic Automatic Temperature Control Module Diagnostic Trouble Code (DTC) Index or the Powertrain Control Module (PCM) Diagnostic Trouble Code Index to continue diagnostics. With Electronic Climate Control
7. If any PCM DTCs are retrieved, and are related to the concern, go to the Symptom Chart to continue diagnostics. Electronic Climate Control
8. If the remote climate control module cannot be accessed by the NGS Tester, go to Pinpoint Test E. E: No Communication With Remote Climate Control Module
a. The RCC module self-test will not detect concerns associated with data link messages like engine coolant temperature or vehicle speed signals. An NGS tester must be used to retrieve these concerns.
b. The RCC module self-test will detect concerns in the system control functions and will display hard DTCs and intermittent DTCs for concerns occurring during system operation. The vehicle interior temperature should be between 4°C (40°F) and 32°C (90°F) when performing the self-test. If the temperatures are not within the specified ranges, false in-car temperature sensor DTCs will be displayed.
c. The self-test can be initiated at any time. Normal operation of the system stops when the self-test is activated.
d. To enter the self-test, press the OFF and FLOOR buttons simultaneously and then press the AUTOMATIC button within two seconds. The display will show a dashed line in the center of the display window. The test may run as long as 30 seconds. Record all DTCs displayed.
e. If any DTCs appear during the self-test, follow the diagnostics procedure given under ACTION for each DTC given.
f. If a condition exists but no DTCs appear during the self-test, refer to the Symptom Chart Condition: EATC System Inoperative, Intermittent or Improper Operation. Electronic Climate Control
g. To exit self-test and retain all intermittent DTCs, push the blue (cooler) button. The control will exit self-test, retain all intermittent DTCs and then turn OFF (display blank).
h. The exit self-test and clear all DTCs, press F-Defrost button. The vacuum fluorescent display window will show 888 and all function symbols for one second. Then, the EATC system will turn OFF (display blank) and all DTCs will be cleared.

Always exit the self-test before powering the system down (system turned OFF). Intermittent DTCs will be deleted after 80 ignition switch ON cycles (after the intermittent condition occurs).