Engine Oil Level Sensor Diagnosis
Engine Oil Level Sensor Diagnosis
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.
Diagnostic Fault Information
Typical Scan Tool Data
Circuit/System Description
The engine oil level sensor/switch is a normally-closed with proper engine oil level. The switch opens when the engine oil level drops below a calibrated level. The engine control module (ECM) monitors the engine oil level signal circuit when the ignition is ON, and the engine is OFF. With the switch in the closed position, the ECM detects a low voltage signal circuit. With the switch in the open position, the ECM detects a high voltage on the signal circuit. When high voltage is detected on the signal circuit, the ECM will send a serial data message to the instrument panel cluster and a message is displayed on the driver information center.
The following information determines the message sent form the ECM to the instrument cluster. The Engine Oil Level Low message is displayed only after the ECM detects a high voltage on the signal circuit for three consecutive ignition cycles, followed by an ignition OFF event from 15 min to greater than 50 min, depending on the engine oil temperature.
The Engine Oil Level Low message is turned OFF when the ECM detects a low voltage on the signal circuit after an ignition OFF event for greater than 90 s, then followed by the ignition ON for less than 1 s.
Reference Information
Schematic Reference
* Engine Mechanical Schematics [1][2]Diagrams
* Instrument Cluster Schematics Instrument Cluster Schematics
Connector End View Reference
Component Connector End Views A/C Compressor Clutch
Description and Operation
* Instrument Cluster Description and Operation Instrument Cluster
* Indicator/Warning Message Description and Operation Indicator/Warning Message
Electrical Information Reference
* Circuit Testing Circuit Testing
* Connector Repairs Connector Repairs
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs Wiring Repairs
Scan Tool Reference
Control Module References Control Module References for scan tool information.
Circuit/System Verification
1. Verify proper engine oil level. Add oil as necessary.
2. Ignition ON, observe the scan tool Engine Oil Level parameter. The reading should be OK and change to Low when the oil level sensor/switch harness connector is disconnected.
Circuit/System Testing
Note: Verify proper engine oil level before continuing with diagnosis.
1. Ignition OFF, disconnect the harness connector at the B35C engine oil level sensor.
2. Ignition OFF for 90 s, test for less than 2 ohms between the ground circuit terminal C and ground.
• If greater than the specified range, test the ground circuit for an open/high resistance.
3. Ignition ON, verify the scan tool Engine Oil Level Warning parameter reads Low.
• If the Oil Level Warning parameter reads OK, test the signal circuit terminal A for a short to ground. If the circuit tests normal, replace the ECM.
Note: If a short to voltage is found on the signal circuit, the fuse in the 3 A jumper wire will open.
4. Ignition ON, install a 3 A fused jumper wire between the signal circuit terminal A and the ground circuit terminal C. Verify the scan tool Engine Oil Level Warning parameter reads OK.
• If the Engine Oil Level parameter reads Low, test the signal circuit terminal A for an open/high resistance. If the circuit tests normal, replace the K20 ECM.
5. If all circuits test normal, test or replace the B35C engine oil level temperature sensor.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the repair.
* Engine Oil Level Sensor and/or Switch Replacement (RWD) Engine Oil Level Sensor and/or Switch Replacement (RWD)Engine Oil Level Sensor and/or Switch Replacement (AWD) Engine Oil Level Sensor and/or Switch Replacement (AWD)
* Control Module References Control Module References for the ECM replacement, programming, and setup