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 below and look for the results indicated.
Step 1 - 14:
Step 15 - 18:
If any of these settings does not produce the correct results, perform the following diagnostic procedure.