Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
The car's computer is having trouble controlling the amount of fuel going to the engine because there's a problem with the wiring.
This code indicates a problem with the electrical circuit that controls the fuel volume regulator, specifically a short circuit.
The P12C0 code is triggered when the Engine Control Module (ECM) detects a short circuit in the control circuit for the fuel volume regulator 'B'. This can affect the regulator's ability to properly manage the fuel supply to the engine.
• Check Engine Light is on
• Poor fuel economy
• Engine stalling or hesitation
• Damaged or frayed wiring
• Faulty fuel volume regulator
• Bad ECM
ECM: Engine Control Module, the computer that manages engine functions.
Short Circuit: An electrical circuit that allows current to travel along an unintended path.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage.
• Test the fuel volume regulator for proper operation.
• Repair or replace damaged wiring.
• Replace the faulty fuel volume regulator.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Wiring repair tools
$150 - $500
Moderate
• Chevrolet Silverado
• GMC Sierra
• Cadillac Escalade
• Regularly inspect wiring for damage.
• Ensure proper maintenance of the fuel system.
• Use quality fuel to avoid system contamination.
Engine Performance
• Avoid driving long distances until the issue is fixed.
• Get a professional diagnosis to prevent further damage.
Check if the vehicle's powertrain warranty covers fuel system components.
This code has been associated with vehicles experiencing fuel delivery issues due to electrical faults.
Moderate – Should be addressed soon to avoid potential engine performance issues.
Driving with this code may lead to increased emissions and potential safety risks.
• Engine running
• Fuel system pressurized
The fuel volume regulator is typically located near the fuel rail or fuel pump.
Q: Can I drive with a P12C0 code?
A: It's not recommended to drive for long periods with this code as it can affect engine performance.
Q: Will a P12C0 code cause my car to fail emissions tests?
A: Yes, this code can cause increased emissions, potentially leading to a failed emissions test.
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