B1031-EVAPORATOR FIN TEMPERATURE SENSOR CIRCUIT LOW (CCN)
For a complete wiring diagram Refer to Section 8W.
- When Monitored:
With the ignition on.
- Set Condition:
If the Evaporator Temperature Sensor input is out of range toward the low voltage threshold.
| Possible Causes |
| (C21) EVAPORATOR TEMPERATURE SENSOR SIGNAL CIRCUIT SHORTED TO GROUND |
| (C21) EVAPORATOR TEMPERATURE SENSOR SIGNAL CIRCUIT SHORTED TO (C121) SENSOR GROUND CIRCUIT |
| EVAPORATOR TEMPERATURE SENSOR |
| INSTRUMENT CLUSTER (CCN) |
NOTE: This DTC must be active for the results of this test to be valid. Do not perform this test if this DTC is stored. Refer to HVAC System Test (ATC) for stored DTC test procedures.
Diagnostic Test
1. CHECK FOR DTC B1031–EVAPORATOR FIN TEMPERATURE SENSOR CIRCUIT LOW WITH EVAPORATOR TEMPERATURE SENSOR HARNESS CONNECTOR DISCONNECTEDTurn the ignition off.
Disconnect the Evaporator Temperature Sensor harness connector.
Turn the ignition on.
With the scan tool, erase DTCs.
Turn the ignition off, wait 10 seconds, and turn the ignition on.
With the scan tool, read DTCs.
Does the scan tool display: B1031–EVAPORATOR FIN TEMPERATURE SENSOR CIRCUIT LOW?
Yes
- Go To 2
No
- Replace the Evaporator Temperature Sensor in accordance with the Service Information.
- Perform the BODY VERIFICATION TEST – VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE).
2. CHECK (C21) EVAPORATOR TEMPERATURE SENSOR SIGNAL CIRCUIT FOR A SHORT TO GROUND
Turn the ignition off.
Disconnect the Cluster (CCN) C3 harness connector.
Measure the resistance of the (C21) Evaporator Temperature Sensor Signal circuit between ground and the Cluster (CCN) C3 harness connector.
Does the ohm meter read open circuit?
Yes
- Go To3
No
- Repair the (C21) Evaporator Temperature Sensor Signal circuit for a short to ground.
- Perform the BODY VERIFICATION TEST – VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE).
3. CHECK (C21) EVAPORATOR TEMPERATURE SENSOR SIGNAL CIRCUIT FOR A SHORT TO (C121) SENSOR GROUND CIRCUIT
Disconnect the Cluster (CCN) C4 harness connector.
Measure the resistance between the (C21) Evaporator Temperature Sensor Signal circuit in the Cluster (CCN) C4 harness connector and the (C121) Sensor Ground circuit in the Cluster (CCN) C3 harness connector.
Does the ohm meter read open circuit?
Yes
- Replace the Cluster (CCN) in accordance with the Service Information.
- Perform the BODY VERIFICATION TEST – VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE).
No
- Repair the (C21) Evaporator Temperature Sensor Signal circuit for a short to the (C121) Sensor Ground circuit.
- Perform the BODY VERIFICATION TEST – VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE).