DTC Troubleshooting: 1

DTC indicator 1:  An Open in the Air Mix Control Motor Circuit

1.Clear the DTC.

2.Turn the ignition switch OFF, and then ON (II).

3.Do the self-diagnostic with the heater control panel.

4.Check for DTCs.

Is DTC 1 indicated?


YES - Go to 5.


NO - Intermittent failure, check for loose wires or poor connections on the air mix control motor circuit.n


5.Turn the ignition switch OFF.

6.Test the air mix control motor.

Is the air mix control motor OK?


YES - Go to 7.


NO - Replace the air mix control motor.n


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

8.Disconnect the heater control panel 24P connector.

9.Check for continuity between the following terminals of the heater control panel 24P connector and the air mix control motor 7P connector.

24P: 7P: 
No. 1 No. 5 
No. 13 No. 7 
No. 18 No. 3 
No. 19 No. 2 
No. 20 No. 1 

 

Is there continuity?


YES - Check for loose wires or poor connections at the heater control panel 24P connector and at the air mix control motor 7P connector. If the connections are good, substitute a known-good heater control panel and recheck. If the symptom/indication goes away, replace the original heater control panel.n


NO - Repair any open in the wires between the heater control panel and the air mix control motor.n