Manufacturer Code Charts: 8

HVAC DTC Troubleshooting: 8

DTC indicator 8:

An Open in the Evaporator Temperature Sensor 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 How To Troubleshoot The Heating And A/C Systems (Without Climate Control).

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 evaporator temperature sensor circuit.�

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

5. Remove the evaporator temperature sensor Service and Repair and test it Evaporator Temperature Sensor Test.

Is the evaporator temperature sensor OK?

YES -

Go to step 6.

NO -

Replace the evaporator temperature sensor Service and Repair.�

6. Disconnect the HVAC control unit 28P connector.

7. Check for continuity between the HVAC control unit 28P connector terminal No. 9 and the evaporator temperature sensor 2P connector terminal No. 2.





Is there continuity?

YES -

Go to step 8.

NO -

Repair an open in the wire between the HVAC control unit and the evaporator temperature sensor.�

8. Check for continuity between the HVAC control unit 28P connector terminal No. 19 and the evaporator temperature sensor 2P connector terminal No. 1.





Is there continuity?

YES -

Check for loose wires or poor connections at the HVAC control unit 28P connector and at the evaporator temperature sensor 2P connector. If the connections are good, substitute a known-good HVAC control unit, 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 between the HVAC control unit and the evaporator temperature sensor.�