Initial Inspection and Diagnostic Overview

1. Verify the vehicle owner's original concern by operating the electronic automatic temperature control to duplicate the concern.

2. Inspect to determine if one of the following mechanical or electrical concerns apply:









3. If the concern(s) remains after the inspection, perform the following Quick Test(s):

NOTE: Self diagnostics should be run in ambient temperatures of at least 10°C (50° F).

^ Turn ignition switch to RUN position.

^ Turn knob to FLOOR mode on control assembly.

^ Turn blower knob to AUTO.

^ Push both COOL and OUTSIDE TEMP buttons simultaneously, then press WARM button.

^ After about 20 seconds, a code will appear in the window. Refer to the Error Code key to identify the error.

NOTE: Display will be blank during testing.

^ To exit the diagnostics function press COOL button. When the control assembly is turned back on, the A/C air temperature control door will self-calibrate for 20 seconds.








4. If no DTCs are generated as a result of Quick Test (88°F°C code is displayed). Determine the symptom(s) and proceed to the following Symptom Chart.