Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This means the car's computer is having trouble getting a signal from a part that helps it know how the engine is spinning. It's like trying to watch TV with a bad signal.
The engine control module (ECM) is not receiving a proper signal from the crankshaft position sensor B, indicating a low voltage condition.
The P0387 code is triggered when the ECM detects a low voltage signal from the crankshaft position sensor B. This sensor monitors the position and rotational speed of the crankshaft, which is crucial for engine timing and operation. A low signal can disrupt engine performance.
• Engine may not start
• Poor engine performance
• Check Engine Light illuminated
• Faulty crankshaft position sensor B
• Damaged or corroded wiring or connectors
• ECM malfunction
ECM: Engine Control Module
OBD-II: On-Board Diagnostics, Second Generation
• Use an OBD-II scanner to confirm the code.
• Inspect the crankshaft position sensor B and its wiring for damage.
• Test the voltage and ground at the sensor connector.
• Replace the crankshaft position sensor B if faulty.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Socket set
$100 - $300
Moderate
• Chevrolet Silverado
• Ford F-150
• Toyota Camry
• Regularly inspect and maintain engine sensors.
• Keep wiring and connectors clean and dry.
• Follow scheduled maintenance for the vehicle.
Sensor Issue
• Do not ignore the Check Engine Light.
• Have the vehicle inspected by a professional if unsure.
• Avoid driving the vehicle if engine performance is severely affected.
Check with the vehicle manufacturer for possible warranty coverage on engine sensors.
The P0387 code has been associated with sensor issues in various vehicle models, often due to wiring or sensor failure.
Moderate – It should be addressed soon to prevent further engine issues.
Ignoring this code can lead to engine performance issues and potential safety hazards.
• Engine running
• Vehicle in a safe, stationary position
The crankshaft position sensor B is typically located near the bottom of the engine, close to the crankshaft pulley.
Q: Can I drive with a P0387 code?
A: It's not recommended as it can lead to further engine issues.
Q: What happens if I ignore this code?
A: Ignoring it can cause poor engine performance and potential engine damage.
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