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 refrigerant.
^ Damaged drive belt.

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 a concern remains after the inspection, use the Rotunda New Generation Star (NGS) Tester 007-00500, connected to the Data Link Connector (DLC), to retrieve continuous Diagnostic Trouble Codes (DTCs) and to execute Self Test Diagnostics for the electronic automatic temperature control module.
5. If self test is passed and no DTCs are retrieved, go to the Symptom Chart to continue diagnostics. Electronic Climate Control
6. If DTCs are retrieved, go to the DTC Reference Chart to continue diagnostics.
7. If the electronic automatic temperature control module cannot be accessed by the NGS Tester, go to Pinpoint Test E. E: No Communication With EATC Module
^ The EATC On-Board Diagnostic will detect concerns in the system control functions found during the On-Board Diagnostic and will display DTCs and intermittent DTCs for concerns occuring during system operation. The vehicle interior temperature should be between 16°(60°F) and 27° (80°F) when performing the On-Board Diagnostic. If the temperatures are not within the specified ranges, false in-car temperature sensor error codes will be displayed. Record all error codes displayed during the test.
^ If any DTCs appear during the On-Board Diagnostic, follow the diagnostics procedure given under ACTION for each DTC given.
^ If a condition exists but no DTCs appear during the On-Board Diagnostic, refer to the Symptom Chart Condition: EATC System Inoperative, Intermittent or Improper Operation. Electronic Climate Control
^ The On-Board Diagnostic can be initiated at any time with any resulting DTCs displayed. Normal operation of the system stops when the On-Board Diagnostic is activated.
^ To enter the On-Board Diagnostic, press the OFF and FLOOR buttons simultaneously and then press the AUTOMATIC button within two seconds. The display will show a pulse tracer going around the center of the display window. The test may run as long as 30 seconds.
^ To exit On-Board Diagnostic and retain DTCs, push the blue (cooler) button. The control will exit On-Board Diagnostic, retain all DTCs and then turn OFF (display blank).