Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's computer is having trouble reading the electricity level from the car's generator or alternator.
The P063A code indicates that the vehicle's powertrain control module (PCM) has detected a problem with the voltage sensing circuit for the generator or alternator.
The PCM monitors the voltage output from the generator to ensure it is within the specified range. If the voltage is too high or too low, or if the circuit is open or shorted, the PCM will set the P063A code. This can affect the charging system's ability to maintain the battery's charge and supply power to the vehicle's electrical systems.
• Battery warning light on the dashboard
• Dimming or flickering lights
• Electrical accessories not working properly
• Faulty alternator
• Damaged or corroded wiring or connectors
• Faulty PCM or voltage regulator
PCM: Powertrain Control Module
DTC: Diagnostic Trouble Code
• Check for any other diagnostic trouble codes (DTCs) and address them first.
• Inspect the alternator and battery for obvious signs of damage.
• Test the voltage output of the alternator using a multimeter.
• Repair or replace damaged wiring or connectors.
• Replace the alternator if it is faulty.
• Replace the PCM if it is determined to be at fault.
• Multimeter
• OBD-II scanner
• Basic hand tools
$200 - $600
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regularly check and maintain the battery and alternator.
• Ensure all electrical connections are clean and secure.
• Replace worn-out belts that drive the alternator.
Sensor Issue
• Avoid using electrical accessories until the issue is resolved.
• Have the charging system inspected by a professional mechanic.
Check with the vehicle manufacturer for specific warranty coverage related to the charging system.
This code has been reported in various models with aging alternators or poor maintenance of the electrical system.
Moderate – While the vehicle may still run, it could lead to battery drain and potential stalling.
Ignoring this code could lead to vehicle stalling, which poses safety risks. It is advisable to address it promptly.
• Engine running
• Electrical load applied (e.g., lights, radio)
The alternator is usually located at the front of the engine, driven by the serpentine belt.
Q: Can I drive with a P063A code?
A: You might be able to drive for a short time, but it's not recommended as it could lead to battery drain and stalling.
Q: How do I clear a P063A code?
A: After repairs, use an OBD-II scanner to clear the code, but ensure the issue is fixed first.
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