Fault code lookup

ChassisC1639

Caution

Severity: Caution - get it checked when you can

Inconsistency between ignition switch positive and master wake-up transmitted by Built-in System Interface (BSI)

5 brands affected · Description from Toyota 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 5

BrandCodeDescriptionSystem
DFFSC1639Main wake-up signal error BrandChassis
HyundaiC1639No description available Chassis
MitsubishiC1639No description available Chassis
SuzukiC1639Communication Error From RBS Control Module To ABS / ESPControl Module BrandChassis
ToyotaC1639Inconsistency between ignition switch positive and master wake-up transmitted by Built-in System Interface (BSI) 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 10

These 7-character codes are manufacturer-specific variants of C1639 and may be reported by some scan tools.

BrandCodeDescriptionSystem
SsangYongC163908CAN communication: Front Radar Module (FRM) message error BrandChassis
Mercedes-BenzC163943Diagnostic certificates missing in memory (NVM) BrandChassis
Mercedes-BenzC163944Write access to NVM failed BrandChassis
Mercedes-BenzC163946NVM Integrity Failed - CRC of NVM block erroneous BrandChassis
Mercedes-BenzC16394BOvertemperature in Radar sensor BrandChassis
Mercedes-BenzC163956The combination of HW and SW is incorrect. BrandChassis
Mercedes-BenzC163996Internal error occurred BrandChassis
Mercedes-BenzC163998Extreme Overtemperature in Radar sensor BrandChassis
Mercedes-BenzC1639FARFCOM Module over temperature BrandChassis
Mercedes-BenzC1639FFFlexRay latency violation BrandChassis

6Related codes

Browse Cxxx codes or C163xx codes.

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