Manufacturer Code Charts: 8

HVAC DTC Troubleshooting: 8

DTC indicator 8:

A Short in the Recirculation 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 8 indicated?

YES -

Go to step 4.

NO -

Intermittent failure. Check for loose wires or poor connections on the recirculation control motor circuit.

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

5. Test the recirculation control motor Recirculation Control Motor Test.

Is the recirculation control motor OK?

YES -

Go to step 6.

NO -

Replace the recirculation control motor Recirculation Control Motor Replacement.

6. Disconnect the recirculation 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. 17 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 recirculation control motor.

NO -

Go to step 9.

9. Check for continuity between HVAC control unit 24P connector terminals No. 17 and No. 24.





Is there continuity?

YES -

Repair a short in the wires between the HVAC control unit and the recirculation 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.17 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 recirculation control motor. This short may also damage the 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 recirculation control motor runs, replace the original HVAC control unit HVAC Control Unit Removal/Installation.