P0387 Code - Crankshaft Position Sensor 'B' Circuit Low Input
Quick Answer
The Crankshaft position sensor also known as the crank position sensor is an electronic device used in an engine to record the rate at which the crankshaft is spinning. Common causes include Faulty crankshaft position sensor, Crankshaft position sensor harness is open or shorted, Crankshaft position sensor circuit poor electrical connection. 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, Crankshaft position sensor harness is open or shorted, Crankshaft position sensor circuit poor electrical connection.
- 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.
Code P0387 Description
When the engine is running, the high and low parts of the teeth cause the gap with the sensor to change. The changing gap causes the magnetic field near the sensor to change. The change in the magnetic field cause the voltage from the sensor to change.
What are the Possible Causes of the DTC P0387?
- Faulty crankshaft position sensor
- Crankshaft position sensor harness is open or shorted
- Crankshaft position sensor circuit poor electrical connection
- Signal plate may be damage
- Starter motor may be faulty
- Starting system circuit
- Dead or weak battery
How to Fix the DTC P0387?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
Code Tech Notes
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P0387 code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.
Need more information about the P0387 code?
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Need Help with the Code?
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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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