Damaged or corroded wiring in the brake booster motor circuit, such as a short to ground or an open circuit; Faulty brake booster motor with a shorted or open phase winding; Poor electrical connection at the motor connector or the control module connector; Internal failure in the brake booster control module, such as a driver circuit fault; Water intrusion or contamination in the motor or connector causing low resistance; Loose or damaged ground connection for the brake booster motor circuit

DTC codes / C05xx · Brakes, steering and suspension / C0580

C0580Brake Booster Motor A Phase U-V-W Circuit Low

Q: What does code C0580 mean?

Brake Booster Motor A Phase U-V-W Circuit Low. C0580 indicates that the brake booster motor's three-phase winding circuit has a low voltage condition on one or more phases, meaning the control module detected voltage below the expected threshold on the U, V, or W phase. This points to a problem in the motor circuit, such as a short to ground, a faulty motor winding, or a wiring issue, which can prevent the brake booster from assisting properly.

C0580 indicates that the brake booster motor's three-phase winding circuit has a low voltage condition on one or more phases, meaning the control module detected voltage below the expected threshold on the U, V, or W phase. This points to a problem in the motor circuit, such as a short to ground, a faulty motor winding, or a wiring issue, which can prevent the brake booster from assisting properly.

SystemChassis

Code typeGeneric (all makes)

SeverityHigh

Fix difficultyProfessional

AreaBrakes, steering and suspension

Symptoms you may notice

Illumination of the brake system warning light or ABS (Anti-lock Braking System) light on the dashboard
Often no symptoms besides the warning light, especially if the fault is intermittent
Reduced brake assist, requiring harder pedal pressure to stop the vehicle
A noticeable decrease in braking performance or a spongy brake pedal feel
Audible clicking or whirring noises from the brake booster area when the brake pedal is pressed
Possible activation of the fail-safe mode, limiting vehicle speed or disabling certain brake functions

Common causes, most likely first

Damaged or corroded wiring in the brake booster motor circuit, such as a short to ground or an open circuit
Faulty brake booster motor with a shorted or open phase winding
Poor electrical connection at the motor connector or the control module connector
Internal failure in the brake booster control module, such as a driver circuit fault
Water intrusion or contamination in the motor or connector causing low resistance
Loose or damaged ground connection for the brake booster motor circuit

How to diagnose and fix it

Perform a visual inspection of the brake booster motor wiring and connectors for damage, corrosion, or loose pins
Use a digital multimeter to check for continuity and resistance in each phase of the motor circuit, comparing to specifications
Check for short to ground on each phase wire by measuring resistance between the wire and chassis ground
Inspect the motor connector for signs of overheating or water intrusion and clean or repair as needed
Test the brake booster motor directly by applying power and ground to the motor terminals to verify operation
If the motor tests faulty, replace the brake booster motor assembly according to the manufacturer's procedure
If the motor and wiring are good, diagnose the control module for internal faults and replace if necessary

Common misdiagnosis traps for C0580

A low voltage code on a motor phase circuit is often caused by a simple wiring issue, such as a chafed wire shorting to ground, rather than a failed motor or module.
Technicians sometimes replace the brake booster motor only to find the connector pins are corroded or pushed back, so always perform a thorough connector inspection first.
The code can set intermittently due to vibration or temperature changes, so a wiggle test of the harness while monitoring live data can reveal the fault.
On some vehicles, a weak battery or charging system can cause low voltage codes across multiple modules, so verify battery voltage and ground integrity before condemning the motor.
The brake booster motor is part of the electronic brake system, and a fault here may also trigger other codes like C0581 or C0582, so scan all modules to avoid missing related issues.

Can I keep driving with C0580?

If the brake warning light is on and you notice reduced braking performance, avoid driving the vehicle and have it towed to a repair shop. If the light is on but braking feels normal, drive cautiously to the nearest service center, avoiding heavy braking or high speeds.

Tools that help

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Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.