Fault code lookup

ChassisC0300

Caution

Severity: Caution - get it checked when you can

Rear Speed Sensor Malfunction

8 brands affected · Description from GM data.

Key terms: 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

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

  1. Faulty wheel speed sensor
  2. Damaged sensor ring or wiring
  3. Faulty ABS module
  4. Low brake fluid
  5. Wheel bearing damage

3Can I drive?

Caution · drive with care

If the code names an airbag or SRS system, the airbag may not deploy in a crash: have it diagnosed promptly. If it names electric power steering, the assist may fail and the steering can become heavy: stop safely if that happens. If it names the brakes or park brake, have it checked before driving when braking feels abnormal. Otherwise ABS and stability control may be disabled: drive carefully, especially in wet conditions, and have it checked soon.

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 8

BrandCodeDescriptionSystem
Ashok Leyland CVC0300No description available Chassis
DaewooC0300No description available Chassis
GMC0300Rear Speed Sensor Malfunction BrandChassis
HoldenC0300Transfer Case Rear Output Shaft Speed Sensor BrandChassis
IsuzuC0300No description available Chassis
OpelC0300Rear Speed Sensor Malfunction BrandChassis
PeugeotC0300No description available Chassis
SaabC0300Rear Speed Sensor Malfunction BrandChassis

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.

5Extended variant codes 1

These 7-character codes are manufacturer-specific variants of C0300 and may be reported by some scan tools.

BrandCodeDescriptionSystem
Mercedes-BenzC030000The internal Valve-Driver-ASIC register is not matching with the current actuation during the ValveActuationRegisterTest. BrandChassis

6Related codes

Browse Cxxx codes or C030xx codes.

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