P0387 Code - Crankshaft Position Sensor 'B' Circuit Low Input
Quick Answer
The OBD-II trouble code P0387 indicates that there is a problem with the crankshaft position sensor 'B' circuit, specifically a low input signal. Common causes include Faulty crankshaft position sensor, Damaged wiring or connectors in the sensor circuit, Corrosion or poor connections in the sensor circuit. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
- What it means
- P0387 indicates Crankshaft Position Sensor 'B' Circuit Low Input.
- Common causes
- Common causes include Faulty crankshaft position sensor, Damaged wiring or connectors in the sensor circuit, Corrosion or poor connections in the sensor circuit.
- Severity
- High - diagnose this code as soon as possible.
- Can I drive?
- Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
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Code P0387 Description
The OBD-II trouble code P0387 indicates that there is a problem with the crankshaft position sensor 'B' circuit, specifically a low input signal. The crankshaft position sensor is a critical component of the engine management system, responsible for monitoring the position and speed of the crankshaft. This information is essential for the engine control module (ECM) to determine the ignition timing and fuel injection strategy.
Common Causes of P0387
- Faulty crankshaft position sensor
- Damaged wiring or connectors in the sensor circuit
- Corrosion or poor connections in the sensor circuit
- Malfunctioning ECM
- Engine overheating leading to sensor damage
Symptoms of P0387
- Engine misfires or rough idling
- Difficulty starting the engine
- Decreased fuel efficiency
- Engine stalling
- Check Engine Light illuminated
How to Fix P0387
- Diagnose the root cause by performing a thorough inspection of the crankshaft position sensor, wiring, and connectors.
- Test the sensor's output using a multimeter to verify if it is within the manufacturer's specified range.
- Replace the faulty crankshaft position sensor if necessary.
- Repair or replace any damaged wiring or connectors in the sensor circuit.
- Clear the trouble code from the ECM and perform a test drive to ensure the issue has been resolved.
Cost to Fix P0387
The typical repair costs for addressing a crankshaft position sensor 'B' circuit low input issue can range from $100 to $300, including parts and labor. Keep in mind that the specific diagnosis time and labor rates at auto repair shops can vary significantly based on factors such as location, vehicle make and model, and engine type. It's advisable to obtain quotes from multiple shops and compare prices before proceeding with the repair.
Tech Notes for P0387
When is the Code Detected?
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Code P0387 Information for Specific Makes
- P0387 Mercedes-Benz — Crankshaft Position Sensor 'B' Circuit Low Input
Frequently Asked Questions about P0387 Code
No Frequently Asked Questions about P0387 Code found.
Discuss the causes and fixes for P0387 OBDII Code
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eu tambem pensei que fosse mele mas tinha uma outra falha do pedal de acelerador eletronico que gerou tambem um codigo de falha no sensor de rotação
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