DTC P0197: Engine Oil Temperature Sensor "A" Circuit Low: Notes
1. -
DTC detecting condition:
Immediately at fault recognition
Trouble symptom:
- Hard to start
- Improper idling
- Poor driving performance
Wiring diagram:
Engine Electrical System Ref. to WIRING SYSTEM>ENGINE ELECTRICAL SYSTEM .
CAUTION:
Use the check board when measuring the ECM terminal voltage and resistance. Ref. to ENGINE (DIAGNOSTICS) (H4DO)>GENERAL DESCRIPTION>PREPARATION TOOL>HOW TO USE CHECK BOARD
.
NOTE:
After the faulty parts are repaired or replaced, perform the final check in Basic Diagnostic Procedure. Ref. to ENGINE (DIAGNOSTICS) (H4DO)>BASIC DIAGNOSTIC PROCEDURE>PROCEDURE
.
- CHECK DATA MONITOR
.
- Start the engine.
- Using the Subaru Select Monitor, read the value in [Engine Oil Temperature].NOTE: For detailed operation procedures, refer to "Common (Diagnostics)". Ref. to COMMON (DIAG)>DATA MONITOR .
Is the value of [Engine Oil Temperature] 150°C (302°F) or more?
Yes : Go to 2 .
No : Even if DTC is detected, the circuit has returned to a normal condition at this time.
Reproduce the failure, and then perform the diagnosis again.
NOTE: In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause. - CHECK HARNESS BETWEEN ECM AND ENGINE OIL TEMPERATURE SENSOR CONNECTOR (SHORT TO GROUND)
.
- Turn the ignition switch to OFF.
- Disconnect the connector from ECM.
- Disconnect the connectors from the engine oil temperature sensor.
- Measure the resistance between the ECM connector and engine ground.
Connector and terminal
(E158) No. 46 - Engine ground:
Is the resistance 1 MΩ or more?
Yes : Replace the engine oil temperature sensor. Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DO)>ENGINE OIL TEMPERATURE SENSOR .
No : Repair the short circuit to ground in the harness between the ECM connector and engine oil temperature sensor connector.