Heating/Air Conditioning

DTC indicator 2: A Short in the Air Mix Control Motor Circuit

1. Clear the DTC.
2. Turn the ignition switch to LOCK (0), and then turn to ON (II).
3. Do the self-diagnostic with the HVAC control unit.
4. Check for DTCs.

Is DTC 2 indicated?

YES - Go to step 5.

NO - Intermittent failure.

5. Turn the ignition switch to LOCK (0).
6. Test the air mix control motor.

Is the air mix control motor OK ?

YES - Go to step 7.

NO - Replace the air mix control motor.

7. Disconnect the air mix control motor 7P connector.
8. Disconnect the HVAC control unit 24P connector.
9. Check for continuity between body ground and the HVAC control unit 24P connector No. 1, 13, and 18 terminals individually.






Is there continuity?

YES - Repair short to body ground in the wires between the HVAC control unit and the air mix control motor.

NO - Go to step 10.

10. Check for continuity between the HVAC control unit 24P connector terminals as follows.






Is there continuity between any of the terminals?

YES - Repair short in the wires.

NO - Go to step 11.

11. Turn the ignition switch to ON (II), and measure the same terminals for voltage to body ground.






Is there battery voltage?

YES - Repair short to power in the wires between the HVAC control unit and the air mix control motor. This short may also damage the HVAC control unit. Repair the 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, replace the original HVAC control unit.