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P0196



DTC P0196

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview
* Review Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC P0196
- Engine Oil Temperature (EOT) Sensor Performance

Diagnostic Fault Information






Circuit/System Description

The engine oil temperature (EOT) sensor is a variable resistor. The EOT sensor measures the temperature of the engine oil. Monitoring the engine oil temperature input is necessary for optimal control of the cam phasers. The oil temperature is monitored from dual function oil level switch and temperature sensor located in the oil pan. The EOT sensor has a signal circuit and a low reference circuit. The engine control module (ECM) supplies bias 5 volts on the EOT signal circuit, and a ground for the EOT low reference circuit. When the EOT sensor is cold, the sensor resistance is high. When the engine oil temperature increases, the sensor resistance decreases. With high sensor resistance, the ECM detects a high voltage on the EOT signal circuit. With lower sensor resistance, the ECM detects a lower voltage on the EOT signal circuit.

Conditions for Running the DTC

* DTCs P0101, P0102, P0102, P0111, P0112, P0113, P0116, P0117, P0118, P0128, P0197, P0198, P0500, and P2610 are not set.
* The engine is running.
* The engine coolant temperature (ECT) is between 45-95°C (113-203°F).
* The start-up ECT is between -7 and +105°C (+19.4 and +221°F).
* The calculated oil temperature is greater than 70°C (158F).
* The intake air temperature (IAT) sensor is less than 30°C (86°F).
* DTC P0196 runs continuously within the enabling conditions.

Conditions for Setting the DTC

Cold Start Fail Test

At start-up, after a 10 hour engine soak time, the EOT is greater than 30°C (54°F) higher or lower than the ECT sensor, and the difference between start-up temperature for the ECT and IAT is less than 16°C (29°F).

OR

The difference between start-up EOT and the start-up ECT is greater than 16°C (29°F) or the difference between the start-up EOT and the start-up IAT is greater than 16°C (29°F).

Continuous Fail Test

The difference between the calculated oil temperature and the actual oil temperature is greater than 40°C (72°F).

Action Taken When the DTC Sets

DTC P0196 is a Type B DTC.

Conditions for Clearing the MIL/DTC

DTC P0196 is a Type B DTC.

Diagnostic Aids

* An IAT sensor that is skewed lower at various ambient temperatures, due to more resistance than is normal, can widen the spread between the two sensors and cause this DTC to set. Measure and record the resistance of the IAT sensor and EOT sensor at various ambient temperatures, and then compare those measurements to the Temperature vs. Resistance Table. Refer to Temperature Versus Resistance.
* Inspect the IAT and EOT sensors terminals, for corrosion or a poor connection.

Circuit/System Verification

1. If DTC P0112, P0113, P0116, P0117, P0118, P0197, or P0198 are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle. Diagnostic Trouble Code Descriptions
2. Ignition ON, observe the scan tool Engine Oil Temperature Calculated and the Engine Oil Temperature Sensor parameters. The readings should be within 30°C (54°F) of each other.

Important: Perform the following verification procedure only if the ignition has been OFF for 10 hours or more.

3. Ignition ON, observe the scan tool IAT Sensor, ECT Sensor, and Engine Oil Temperature Sensor parameters. The readings should be within 15°C (27°F) of each other and also the ambient temperature.
4. Engine running, observe the DTC information with a scan tool. DTC P0196 should not set.
5. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame Records data.

Circuit/System Testing

Important: You must perform the Circuit/System Verification before proceeding with the Circuit/System Testing.

1. Ignition OFF, disconnect the harness connector at the MAF/IAT sensor.
2. Test for less than 5 ohms of resistance between the low reference circuit terminal B and ground.

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

3. Disconnect the harness connector at the EOT sensor.
4. Test for less than 5 ohms of resistance between the low reference circuit terminal C and ground.

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

5. Disconnect the harness connector at the ECM.
6. Test for less than 5 ohms of resistance between the IAT signal circuit terminal A and the corresponding terminal C2-67 at the ECM.

If greater than the specified range, repair the high resistance on the signal circuit.

7. Test for less than 5 ohms of resistance between the EOT signal circuit terminal B and the corresponding terminal C2-65 at the ECM.

If greater than the specified range, repair the high resistance on the signal circuit.

8. If all circuits test normal, test the IAT sensor.

If the IAT sensor tests normal, replace the engine oil level sensor and/or switch assembly.

Component Testing

Compare the resistance of the IAT sensor to the temperature vs resistance table.

If the difference is more than 9 percent, replace the MAF/IAT sensor.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests

* Engine Oil Level Sensor and/or Switch Replacement
* Mass Airflow Sensor/Intake Air Temperature Sensor Replacement
* Control Module References for ECM replacement, setup, and programming Programming and Relearning