Diagnostic Instructions

DTC Descriptors

DTC P0196: Engine Oil Temperature (EOT) Sensor Circuit Performance

DTC P0197: Engine Oil Temperature (EOT) Sensor Circuit Low Voltage

DTC P0198: Engine Oil Temperature (EOT) Sensor Circuit High Voltage

Diagnostic Fault Information

Circuit	Short to Ground	High Resistance	Open	Short to Voltage	Signal Performance
EOT Sensor Signal	P0198	P0196, P0197	P0197	P0197	P0196
EOT Low Reference	--	P0196, P0197	P0197	--	P0196

Typical Scan Tool Data

Engine Oil Temperature Sensor

Circuit	Short to Ground	High Resistance	Short to Voltage
Operating Conditions: Engine running Parameter Normal Range: Varies with engine oil temperature
EOT Sensor Signal	172°C (341°F)	-40°C (-40°F)	-40°C (-40°F)
Low Reference	--	-40°C (-40°F)	-40°C (-40°F)

Circuit/System Description

The engine oil temperature (EOT) sensor is a variable resistor that measures the temperature of the engine oil. The engine control module (ECM) supplies 5 volts on the EOT signal circuit, and a ground to the low reference circuit.

Monitoring the engine oil temperature is necessary for optimal control of the cam actuators. The oil temperature is monitored from the dual function oil level switch and temperature sensor located in the oil pan.

Conditions for Running the DTC

P0196

P0197 and P0198

Conditions for Setting the DTC

P0196

The ECM detects the actual EOT is 40°C (104°F) colder than the calculated EOT of the controller, for greater than 4 seconds or a cumulative time of 30 seconds.

P0197

The ECM detects the EOT is colder than -35°C (-31°F) for greater than 4 seconds or a cumulative time of 30 seconds.

P0198

The ECM detects the EOT is warmer than 170°C (331°F) for greater than 4 seconds or a cumulative time of 30 seconds.

Action Taken When the DTC Sets

DTCs P0197 and P0198 are Type B DTCs.

Conditions for Clearing the MIL/DTC

DTCs P0197 and P0198 are Type B DTCs.

Reference Information

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Electrical Information Reference

DTC Type Definitions

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Circuit/System Verification

1. Engine operating, observe DTC information with a scan tool. DTCs P0196, P0197, or P0198 should not set.
2. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the EOT sensor.
2. Ignition OFF, remove the fuse that supplies B+ to circuit terminal 56 X2 of the ECM.
3. Test for less than 5 Ω between the low reference circuit terminal C and ground.

⇒	If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the ECM.

4. Install the fuse that supplies B+ to circuit terminal 56 X2 of the ECM.
5. Ignition ON, verify the scan tool Engine Oil temperature Sensor parameter is colder than -35°C (-31°F).

⇒	If greater than the specified range, test the signal circuit terminal B for a short to ground. If the circuit tests normal, replace the ECM.

Note: If the fuse in the jumper wire opens, the signal circuit is shorted to a voltage and the sensor may be damaged.

6. Connect a 3 A fused jumper wire between the signal circuit terminal B and the low reference circuit terminal C. Verify the scan tool EOT Sensor parameter is warmer than 171°C (340°F).

⇒	If less than the specified range, test the signal circuit for a short to voltage or an open/high resistance, if the circuit tests normal, replace the ECM.

7. If all circuits test normal, replace the EOT/oil level sensor assembly.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for ECM replacement, setup, and programming