C05BD

Brake Booster Motor B Position Sensor Supply Circuit Low

Severity

🔴 High

Can you drive?

Limited driving only, diagnose soon

Approx. repair cost

$56–167 (est.)

Symptoms

Increased brake pedal force
The brake system fault indicator is on
Reduced braking performance
Unstable operation of the brake booster

Causes

Broken or damaged wires in the sensor circuit
Bad contacts in the sensor connectors
Brake booster motor position sensor fault B
Problems with the brake control unit (ECU)
Short circuit in the sensor power supply circuit

How to Fix

Check the integrity of wires and contacts in the sensor circuit
Measure the voltage at the brake booster motor position sensor B
Check sensor resistance to manufacturer specifications
Replace brake booster motor position sensor B if necessary
Check and, if necessary, replace the brake control unit (ECU)

Related codes

C05BC C05BE C05BF