Operation CHARM: Car repair manuals for everyone.

DTC Indicator 9

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

1. Turn the ignition switch to LOCK (0), and then ON (II).
2. Do the self-diagnostic with the HVAC control unit.
3. Check for DTCs.

Is DTC 9 indicated?

YES - Go to step 4.

NO - Intermittent failure.

4. Turn the ignition switch to LOCK (0).
5. Remove the evaporator temperature sensor and test it.

Is the evaporator temperature sensor OK?

YES - Go to step 6.

NO - Replace the evaporator temperature sensor.

6. Disconnect the HVAC control unit 28P connector.
7. Check for continuity between body ground and the HVAC control unit 28P connector No. 9 terminal.






Is there continuity?

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

NO - Go to step 8.

8. Check for continuity between the HVAC control unit 28P connector No. 9 and No. 19 terminals.






Is there continuity?

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

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