C057B

Brake Booster Temperature Sensor B Circuit/Open

Severity

⚠️ Medium

Can you drive?

Limited driving only, diagnose soon

Approx. repair cost

$33–167 (est.)

Symptoms

The brake system warning light is on
Reduced braking performance
Activating the emergency brake system
Disabling Brake Assist Features

Causes

Open or short circuit in the sensor wiring harness
Malfunction of the temperature sensor itself
Poor contact in the sensor connector
Contact corrosion
Malfunction of the brake system control unit

How to Fix

Check the voltage and resistance in the sensor circuit
Inspect the arrness for damage
Check contacts in connectors
If necessary, replace the temperature sensor
Flash or replace the control unit (in rare cases)

Related codes

C057A C05instructions U0121