With A/C

HVAC DTC Troubleshooting: 3

DTC indicator 3:

A Problem in the Air Mix Control Linkage, Door, or Motor

1. Turn the ignition switch to LOCK (0), and then turn to ON (II).

2. Do the Self-Diagnostic Function with the HVAC control unit How To Troubleshoot The Heating And A/C Systems.

3. Check for DTCs.

Is DTC 3 indicated?

YES -

Go to step 4.

NO -

Intermittent failure. Check for damaged wires or poor connections in the air mix control motor circuit.�

4. Turn the ignition switch to LOCK (0).

5. Test the air mix control motor Air Mix Control Motor Test.

Is the air mix control motor OK?

YES -

Go to step 6.

NO -

Replace the air mix control motor Air Mix Control Motor Replacement, or repair the air mix control linkage or door.�

6. Check for continuity between following terminals of the HVAC control unit 24P connector and the air mix control motor 7P connector.









Is there continuity?

YES -

Go to step 7.

NO -

Repair an open in the wire(s) between the HVAC control unit and the air mix control motor.�

7. Check for continuity between body ground and heater control panel 24P connector terminals No. 19 and No. 20 individually.





Is there continuity?

YES -

Repair a short to body ground in the wire(s) between the HVAC control unit and the air mix control motor.�

NO -

Substitute a known-good HVAC control unit, and recheck. If the symptom/indication goes away, replace the original HVAC control unit HVAC Control Unit Removal/Installation (With A/C).�