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 GROUNDEVAPORATOR TEMPERATURE SENSORINSTRUMENT CLUSTER (CCN)
Diagnostic Test1.VERIFY B1031–EVAPORATOR FIN TEMPERATURE SENSOR CIRCUIT LOW IS ACTIVETurn 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 this DTC as active?YesGo To 2NoCheck for an intermittent condition by inspecting the related wiring harness for chafed, pierced, pinched, and partially broken wires. Also, inspect the related
connectors for broken, bent, pushed out, spread, corroded, or contaminated terminals. Repair as necessary.Perform the BODY VERIFICATION TEST – VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE).2.CHECK FOR DTC WITH THE 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 this DTC as active?YesGo To 3.NoReplace the Evaporator Temperature Sensor in accordance with the service information.Perform 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 GROUNDTurn the ignition off.Disconnect the Instrument Cluster (CCN) C3 harness connector.Measure the resistance between ground and the (C21) Evaporator Temperature Sensor Signal circuit and ground.Does the ohm meter read open circuit?YesReplace the Instrument Cluster (CCN) in accordance with the service information.Perform BODY VERIFICATION TEST - VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE).NoRepair the (C21) Evaporator Temperature Sensor Signal circuit for a short to ground.