Improper Air Delivery or No Mode Shift
This procedure provides a test of all functions of the heater/defroster unit.1. Warm up the vehicle.
2. Keep the engine running.
3. Perform the tests outlined in the table and look for the results indicated.
Steps 1 Thru 14:
Steps 15 Thru 18:
If any of these settings does not produce the correct results, perform the diagnostic procedure.