Diagnostic Procedure

DIAGNOSTIC PROCEDURE





NOTE: If Diagnostic Trouble Codes "P0110, (intake air temperature circuit malfunction), "P0115" (engine coolant temperature circuit malfunction) and "P0120" (throttle position circuit malfunction) are output simultaneously, E2 (sensor ground) may be open.

1. Connect the OBDII scan tool or LEXUS hand-held tester and read value of engine coolant temperature.
- If OK check for intermittent problems.
- If -40°C (-40°F) Go to step 2.
- If 120°C (248°F) or more Go to step 4.
2. Check for open in harness or Engine Control Module.
- If not OK proceed to step 3.
- If OK confirm good connection at sensor. If OK. replace Engine Coolant Temperature Sensor.
3. Check for open in harness or Engine Control Module.
- If OK open in harness between Engine Control Module and Engine Coolant Temperature Sensor.
- If not OK confirm connection at Engine Control Module. If OK, replace Engine Control Module.
4. Check for short in harness and Engine Control Module
- If not OK proceed to step 5.
- If OK replace Engine Coolant Temperature Sensor.
5. Check for short in harness or Engine Control Module.
- If OK repair or replace harness or connector.
- If not OK check and replace Engine Control Module.