Impulse sensor
â–¶ How to fix
Pair the units using the special test instrument if necessary. Check the impulse sensor including wiring and connectors.
What you'll see
No driver-visible symptom recorded.
System reaction
No system-reaction text recorded.
Diagnostic depth
Detection
The encrypted signal from the impulse sensor has been detected as being faulty or unknown.
Possible cause
The fault code is set if the tachograph or the impulse sensor are renewed without being paired using one of the special test instruments. The fault code can, however, also be set if communication between the units has been faulty due to short circuits, open circuits or defective impulse sensor.