Diesel Data: Automotive Repair

Recirculation Control Motor Circuit Troubleshooting (Without Climate Control)




Recirculation Control Motor Circuit Troubleshooting

1. Check the No. 30 (10 A) fuse in the under-dash fuse/relay box.

Is the fuse OK?

YES -

Go to step 2.

NO -

Check for a short in the No. 30 (10 A) fuse circuit.�

2. Disconnect the recirculation control motor 7P connector.

3. Turn the ignition switch to ON (II).

4. Measure the voltage between recirculation control motor 7P connector terminal No. 1 and body ground.





Is there battery voltage?

YES -

Go to step 5.

NO -

Repair an open in the wire between the No. 30 (10 A) fuse in the under-dash fuse/relay box and the recirculation control motor.�

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

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

Is the recirculation control motor OK?

YES -

Go to step 7.

NO -

Replace the recirculation control motor Recirculation Control Motor Replacement, or repair the recirculation control linkage or door.�

7. Disconnect the HVAC control unit 30P connector.

8. Check for continuity between body ground and HVAC control unit 30P connector terminals No. 13 and No. 14 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. Turn the ignition switch to ON (II), check the same terminals for voltage between the terminals and body ground.





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 the short to power before replacing the HVAC control unit.�

NO -

Go to step 10.

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

11. Check for continuity between the following terminals of the HVAC control unit 30P connector and the recirculation control motor 7P connector.









Is there continuity?

YES -

Check for loose wires or poor connections at the HVAC control unit 30P connector and the recirculation control motor 7P connector. If the connections are good, substitute a known-good HVAC control unit HVAC Control Unit Removal/Installation (Without Climate Control), and recheck. If the symptom/indication goes away, replace the original HVAC control unit HVAC Control Unit Removal/Installation (Without Climate Control).�

NO -

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