P05DB

Symptoms

• Check Engine Light and/or ABS/ESP Warning Illuminated
• Disabling adaptive cruise control
• Engine start blocking (in some cars, starting is impossible without a signal from the brake sensor)
• Disabling or incorrect operation of the regenerative braking system
• Delayed response when pressing the brake pedal in systems with brake-by-wire

Causes

• Broken wire in the brake pedal position sensor B circuit
• Damage to the sensor connector (corrosion, broken retainer, dropped contact)
• Malfunction of the sensor itself (internal break)
• Moisture ingress into the pedal unit area and corrosion of the contacts
• Mechanical damage to the wiring harness during pedal assembly repair

How to Fix

1. Read fault codes; check related ABS, ESP, cruise control codes
2. Inspect the brake pedal position sensor B and its connector under the pedal unit - the presence of moisture, corrosion, mechanical damage
3. Check the presence of power and ground at sensor connector B with the ignition on
4. Measure the resistance of sensor B or check its signal when pressing the pedal
5. Check the signal wire from the sensor connector to the ECU for a break
6. Replace brake pedal position sensor B or repair wiring

Related codes

Error P05DB by Vehicle Brand