Fault Code 4400

Fault Code 4400

Transverse acceleration sensor (AY sensor)
Actual value of transverse acceleration sensor is evaluated and displays an implausible value

The transverse acceleration sensor and the rate-of-turn sensor are combined in one housing. If a fault is detected in the transverse acceleration sensor, the rate-of-turn sensor must be replaced.

Diagnostic conditions
- Steady forward speed on curves and straight ahead at no less than 20 km/h

Possible cause of fault
- Short circuit to B+/ground or open circuit in control unit circuit
- Transverse acceleration sensor (AY sensor) faulty
- PSM control unit faulty

Affected pins
Pin 8, pin 21 and pin 39

Diagnosis/troubleshooting

Part 1:

Part 2: