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 has detected a problem with the part that helps you brake easily. It's like when a toy's battery is too strong and makes it move too fast.
The P120E code is triggered when the vehicle's control module detects a high voltage condition in the brake booster pump control circuit.
The brake booster pump is responsible for providing additional force to the brake system, making it easier for the driver to apply the brakes. The control circuit ensures the pump operates within specified voltage parameters. A 'high' condition indicates excessive voltage, which can lead to improper brake function.
• Increased effort required to apply brakes
• Brake warning light illuminated
• Unusual noises from the brake system
• Faulty brake booster pump
• Wiring issues such as shorts or opens in the circuit
• Faulty control module
Brake Booster: A device that uses vacuum or hydraulic pressure to assist in applying the brakes.
Control Module: An electronic device that manages various functions of the vehicle.
• Check for any stored trouble codes and clear them to see if P120E returns.
• Inspect the brake booster pump and related wiring for any visible damage.
• Test the voltage and ground connections at the brake booster pump.
• Replace the faulty brake booster pump.
• Repair or replace damaged wiring or connectors.
• Replace the control module if found defective.
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $600
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regular inspection of brake system components
• Ensure proper maintenance of electrical connections
• Replace brake fluid as recommended
Brake System Issue
• Do not ignore the brake warning light.
• Have your brakes inspected by a professional if you notice any changes in braking performance.
Check with your vehicle manufacturer for specific warranty coverage on brake system components.
This code has been associated with issues in vehicles equipped with electronic brake booster systems, particularly in models with advanced braking technology.
High – Brake system issues should be addressed immediately to ensure vehicle safety.
Driving with a malfunctioning brake system can lead to accidents and is unsafe. Address any brake-related issues promptly.
• Vehicle in a safe, stationary position
• Engine running
The brake booster pump is typically located near the brake master cylinder, often on the driver's side of the vehicle.
Q: Can I drive with a P120E code?
A: It's not recommended to drive with this code active, as it indicates a potential issue with the brake system.
Q: How can I reset the P120E code?
A: You can clear the code using an OBD-II scanner, but it's important to fix the underlying issue first.
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