B1387 – OBD-II DTC

OBD-II DTC B1387 – Oil Temperature Sensor Circuit Open

DTC B1387 meaning

DTC B1387 refers to an issue with the oil temperature sensor circuit, specifically indicating that there is an open circuit. This means that the Engine Control Module (ECM) is not receiving a proper signal from the oil temperature sensor, which is crucial for monitoring the engine’s oil temperature for optimal performance and protection.

DTC B1387 symptoms

Common symptoms associated with DTC B1387 may include:

• Illumination of the check engine light
• Inaccurate oil temperature readings
• Engine performance issues
• Potential overheating of the engine

DTC B1387 causes

Several factors can lead to the occurrence of DTC B1387, including:

• Faulty oil temperature sensor
• Damaged wiring or connectors in the sensor circuit
• Corrosion at the sensor connection points
• Issues with the Engine Control Module (ECM)

DTC B1387 seriousness

DTC B1387 can be considered serious as it may lead to engine damage if the oil temperature is not monitored correctly. An open circuit can prevent the ECM from receiving critical information, potentially resulting in overheating or inadequate lubrication.

How to diagnose DTC B1387

To diagnose DTC B1387, follow these steps:

1. Use an OBD-II scanner to confirm the DTC and check for any additional codes.
2. Inspect the oil temperature sensor and its wiring for visible damage or disconnections.
3. Test the resistance of the oil temperature sensor to ensure it is within specifications.
4. Check the continuity of the wiring between the sensor and the ECM.
5. Examine the ECM for any faults or issues that may affect sensor readings.

How to fix DTC B1387 step-by-step instructions

To fix DTC B1387, follow these steps:

1. Disconnect the battery to ensure safety while working on the electrical system.
2. Inspect and repair any damaged wiring or connectors related to the oil temperature sensor.
3. Replace the oil temperature sensor if it is found to be faulty.
4. Reconnect the battery and clear the DTC using an OBD-II scanner.
5. Start the engine and monitor for any reoccurrence of the DTC.

How to erase DTC B1387

To erase DTC B1387, you can follow these steps:

1. Connect an OBD-II scanner to the vehicle’s diagnostic port.
2. Turn on the ignition without starting the engine.
3. Navigate to the option to clear or erase trouble codes on the scanner.
4. Confirm the action to erase the DTC.
5. Disconnect the scanner and start the engine to check if the code returns.

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