No data signal from motion sensor
* Check the wiring and the connector to the motion sensor and the tachograph: - Damaged wiring or connector? - Loose connector? - Poor connection? * Check the component pin assignment for the motion sensor data signal: - Motion sensor: Pin 4 (data signal output). - Tachograph: Pin B4 (data signal input). - Connections between the motion sensor and the tachograph. * Use a test device to pair the motion sensor with the tachograph. * Replace defective components.
What you'll see
No driver-visible symptom recorded.
System reaction
MC20/EV300: * Warning message with error text: "Sensor fault" together with Memory Code 20 is shown in the tachograph display. * The warning message will be displayed repetitively every hour until the cause is withdrawn. * Event stored in the tachograph memory * Event stored and in the inserted tachograph card. * System event in TCO1 CAN message is set to active. * Tachograph warning (amber T) is displayed in the instrument cluster.
Diagnostic depth
Error during motion sensor communication. No valid data signal received from the motion sensor (B4).
* Fault in the cable harness. * Motion sensor is not paired with the tachograph.