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 a part of the car's computer system is getting too much electricity, which can cause problems.
The code P16FB indicates that the voltage in the sensor power supply circuit 'D' is higher than the expected range.
The Engine Control Module (ECM) monitors the voltage levels of various sensor power supply circuits. If the voltage in circuit 'D' exceeds the specified threshold, the ECM triggers the P16FB code. This can affect the performance of sensors connected to this circuit.
• Check Engine Light on
• Erratic engine performance
• Poor fuel efficiency
• Faulty voltage regulator
• Short circuit in the wiring
• Defective ECM
ECM: Engine Control Module
Voltage Regulator: A device that maintains a constant voltage level
• Check the voltage output of the sensor power supply circuit 'D'.
• Inspect wiring and connectors for damage or short circuits.
• Test the ECM for faults.
• Replace or repair faulty wiring.
• Replace the voltage regulator if defective.
• Reprogram or replace the ECM if necessary.
• Multimeter
• OBD-II Scanner
• Basic hand tools
$100 - $500
Moderate
• Chevrolet Malibu
• Buick LaCrosse
• GMC Terrain
• Regular maintenance checks
• Ensure proper electrical connections
• Avoid overloading electrical circuits
Sensor Issue
• Do not ignore the Check Engine Light.
• Have a professional diagnose the issue if unsure.
Repairs may be covered under the vehicle's powertrain warranty.
This code has been reported in vehicles with electrical system modifications or after-market installations.
Moderate – It should be addressed soon to prevent potential damage to the vehicle's electrical system.
Ignoring this code could lead to further vehicle damage and may affect emissions compliance.
• Engine running
• All electrical accessories off
The sensor power supply circuit 'D' is typically located within the vehicle's ECM or fuse box area.
Q: Can I drive with a P16FB code?
A: It's possible, but not recommended as it may lead to further issues.
Q: Will this code affect my car's performance?
A: Yes, it can cause erratic engine behavior and poor fuel efficiency.
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