Manufacturer Code Charts: 2

HVAC DTC Troubleshooting: 2

DTC indicator 2:

A Short in the Air Mix Control Motor Circuit

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

2. Do the Self-Diagnostic Function with the HVAC control unit.

3. Check for DTCs.

Is DTC 2 indicated?

YES -

Go to step 4.

NO -

Intermittent failure. Check for loose wires or poor connections on 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.

6. Disconnect the air mix control motor 7P connector.

7. Disconnect the HVAC control unit 24P connector.

8. Check for continuity between body ground and HVAC control unit 24P connector terminals No. 20 and No. 24 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 -

Go to step 9.

9. Check for continuity between HVAC control unit 24P connector terminals No. 20 and No. 24.





Is there continuity?

YES -

Repair a short in the wires between the HVAC control unit and the air mix control motor.

NO -

Go to step 10.

10. Turn the ignition switch to ON (II), and measure the voltage between body ground and HVAC control unit 24P connector terminals No. 20 and No. 24 individually.





Is there any voltage?

YES -

Repair a short to power in the wire(s) between the HVAC control unit and the air mix control motor. This short may also damage HVAC control unit. Repair a short to power before replacing the HVAC control unit.

NO -

Substitute a known-good HVAC control unit, and recheck. If the symptom/indication goes away, and the air mix control motor runs, replace the original HVAC control unit HVAC Control Unit Removal/Installation.