Evap Temp Sensor Shorted (ATC)

EVAP TEMP SENSOR SHORTED (ATC)

For a complete wiring diagram Consult Diagrams/Electrical

- When Monitored:
With the ignition on.

When executing the Cooldown Test.

- Set Condition:
If the A/C Heater Control detects abnormally low voltage on the (C21) Evaporator Temperature Sensor Signal circuit.





Diagnostic Test

1. CHECK FOR HVAC DTCs
Turn the ignition on.
With the scan tool, read HVAC DTCs.
Does the scan tool display any DTCs?

Yes

- Diagnose and Repair the DTC(s).
- Run the Cooldown Test after the repair is complete.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.

No

- Go To 2

2. EVAPORATOR TEMPERATURE SENSOR
Turn the ignition off.
Disconnect the Evaporator Temperature Sensor harness connector.
Turn the ignition on.
With the scan tool check for DTC's
Does the scan tool display: Evap Temp Sensor Shorted?

Yes

- Go To 3

No

- Replace the Evaporator Temperature Sensor.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.

3. CHECK (C21) EVAPORATOR TEMPERATURE SENSOR SIGNAL CIRCUIT FOR A SHORT TO GROUND




Turn the ignition off.
Disconnect the HVAC Control Head harness connector.
Measure the resistance between the (C21) Evaporator Temperature Sensor Signal circuit and ground.
Does the ohm meter read open circuit?

Yes

- Replace the HVAC Control Head.

No

- Repair the (C21) Evaporator Temperature Sensor Signal circuit for a short to ground.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.