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Diagnostic Trouble Code (DTC) Information






Diagnostic trouble code (DTC) information

Condition





Note! The diagnostic trouble code (DTC) applies only to cars with dynamic stability and traction control (DSTC).

The yaw rate sensor, lateral accelerometer, accelerometer (only AWD) and angle of lean sensor (only RSC) are integrated in the active yaw control sensor. This in turn is connected to the brake control module (BCM) via its own Control area network (CAN) cable. The sensors transmit information to the brake control module (BCM) indicating the size of the yaw angle, the lateral acceleration of the car, the forward acceleration and the car's lateral angle of lean.
Diagnostic trouble code (DTC) BCM-0121, BCM-0125, BCM-0127 or BCM-0129 is stored, depending on the sensor, if the control module registers that the signal from any of the sensors is outside its permitted range.
- BCM-0121: Yaw rate sensor
- BCM-0125: Lateral acceleration sensor
- BCM-0127: Tilt angle sensor
- BCM-0129: Accelerometer.

Substitute value
- Traction control is blocked
- Stability control is blocked
- Active yaw control is blocked
- RSC is blocked (cars equipped with RSC only).

Hint: For information about abbreviations, see Brake system, abbreviations Brake System, Abbreviations.

Possible source
- Interference or noise on the wiring has disrupted the active yaw control sensor calculations
- The power supply to the active yaw control sensor is too low
- Incorrect wheel alignment
- Internal fault in the active yaw control sensor.

Note! This diagnostic trouble code (DTC) is not due to an internal hardware fault in the Brake control module (BCM) and must not be remedied by replacing the control module.

Fault symptom[s]
- The anti-spin warning lamp is lit (up to and including 2002 model year)
- General yellow warning lamp lit (from model year 2003)
- Anti-spin does not function
- The stability control system does not function
- The traction control system does not function.