ChassisC05B9

Serious

Severity: Serious - have it checked soon

Brake booster motor 'A' position sensor supply circuit low

3 brands affected · Description from Toyota data.

Key terms: Boost pressure: extra air pressure made by a turbo or supercharger · ABS: anti-lock braking, which stops the wheels locking · Stability control: helps stop the car skidding · Wheel speed sensor: measures how fast each wheel turns

Safety: This code relates to the braking system or brake assist. Braking may be affected.

1What it means in plain English

A chassis system has a fault, usually ABS, traction control or stability control, but some makes use this range for airbags, electric power steering or park brakes.

2Common causes

Faulty wheel speed sensor
Damaged sensor ring or wiring
Faulty ABS module
Low brake fluid
Wheel bearing damage

3Can I drive?

Serious · drive with care

Have it checked immediately: brakes or brake assistance may be affected. Do not drive if the pedal feels soft or hard, the car pulls when braking, or the brake warning light is on.

This page gives general information. It is not professional advice. For a definite diagnosis and a repair quote, ask a qualified mechanic to inspect the car.

4Brand data 3

Brand	Code	Description	System
Ashok Leyland CV	C05B9	No description available	Chassis
EOBD	C05B9	Bromsservomotor 'A' positionsgivare matningskrets låg Brand	Chassis
Toyota	C05B9	Brake booster motor 'A' position sensor supply circuit low Brand	Chassis

Legend: SAE is the generic J2012 description; Brand is text taken from that manufacturer’s data. Manufacturer rows keep the wording and language of the source data, and non-English text is tagged so screen readers pronounce it correctly.

5Related codes

Browse Cxxx codes or C05Bxx codes.