DTC Troubleshooting: 9

DTC indicator 9:  A Short in the Evaporator Temperature Sensor Circuit

1.Clear the DTC.

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

3.Do the self-diagnostic with the HVAC control unit.

4.Check for DTCs.

Is DTC 9 indicated?


YES - Go to 5.


NO - Intermittent failure.n


5.Turn the ignition switch OFF.

6.Remove the evaporator temperature sensor and test it.

Is the evaporator temperature sensor OK?


YES - Go to 7.


NO - Replace the evaporator temperature sensor.n


7.Disconnect the HVAC control unit 24P connector.

8.Check for continuity between body ground and the HVAC control unit 24P connector terminals No. 2 and No.13 individually.

 

Is there continuity?


YES - Repair short to body ground in the wires between the HVAC control unit and the evaporator temperature sensor.n


NO - Go to 9.


9.Check for continuity between the HVAC control unit 24P connector terminals No. 2 and No. 13.

 

Is there continuity?


YES - Repair short in the wires between the HVAC control unit and the evaporator temperature sensor.n


NO - Substitute a known-good HVAC control unit, and recheck. If the symptom/indication goes away, replace the original  HVAC control unit.n