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 there's a problem with the electrical circuit that controls the fuel injector for cylinder 12 in your car. It's like a light switch that isn't working, so the fuel injector can't do its job properly.
The P315F code indicates that the circuit controlling the high-pressure fuel injector for cylinder 12 is open, meaning there is a break or disconnection in the electrical path.
The P315F code is triggered when the Engine Control Module (ECM) detects an open circuit condition in the high-pressure fuel injector circuit for cylinder 12. This can prevent the injector from delivering the correct amount of fuel, affecting engine performance.
• Engine misfire
• Reduced engine performance
• Check Engine Light illuminated
• Damaged or corroded wiring in the injector circuit
• Faulty fuel injector for cylinder 12
• Bad connection at the injector or ECM
ECM: Engine Control Module
Injector: A device that sprays fuel into the engine's combustion chamber
• Perform a visual inspection of the injector wiring and connectors.
• Use a multimeter to check for continuity in the injector circuit.
• Test the fuel injector for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the faulty fuel injector.
• Ensure all connections are secure and free of corrosion.
• Multimeter
• OBD-II scanner
• Basic hand tools
$200 - $600
Moderate
• BMW 7 Series
• Mercedes-Benz S-Class
• Audi A8
• Regularly inspect and maintain fuel injector connections.
• Use fuel system cleaners to prevent injector clogging.
• Ensure proper engine maintenance schedules are followed.
Engine Performance
• Avoid driving the vehicle until the issue is resolved to prevent further damage.
• Consult a professional mechanic for a thorough diagnosis.
Fuel injectors may be covered under the powertrain warranty. Check with your vehicle manufacturer.
This code is commonly associated with vehicles that have high mileage or have been subjected to harsh driving conditions.
High – This issue can lead to engine damage if not addressed promptly.
Driving with a misfiring engine can be unsafe and may cause further damage to the vehicle.
• Engine at operating temperature
• Vehicle stationary
The fuel injector for cylinder 12 is located on the engine, typically near the intake manifold.
Q: Can I drive with a P315F code?
A: It's not recommended to drive with this code active, as it can lead to further engine damage.
Q: How do I know if my fuel injector is bad?
A: Symptoms of a bad injector include engine misfires, poor fuel economy, and rough idling.
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Universal · Digital multimeter
A solid entry-level multimeter for voltage, continuity, resistance, and basic electrical troubleshooting.
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Universal · Wire connectors and repair kit
Useful when diagnosis points toward damaged wiring, corroded terminals, or connector repairs.
Useful if diagnosis points toward damaged connectors, wiring, or terminal repairs.
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Fitment Required · Vehicle-fitment part
Commonly relevant for misfire, ignition-efficiency, and some drivability-related repairs.
Misfire and ignition-related faults commonly involve spark plugs as part of the repair path.
Check the correct plug type, gap, and engine application for your vehicle.
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Fitment Required · Vehicle-fitment part
Relevant when the fault points toward ignition-coil performance or cylinder-specific ignition issues.
Some ignition faults involve coil performance or cylinder-specific coil problems.
Match the coil to your engine and confirm the failed component before ordering.
View options on AmazonThese parts may be related to this fault category, but a code by itself does not confirm exact fitment or guarantee that replacing a part will solve the problem.