Road speed signal from tachograph.
â–¶ How to fix
Check whether anything is incorrectly connected to pin B7.Check pin B7 on the tachograph.Check the cable harness between the tachograph and the component connected to pin B7 for a short-circuit to ground or +24 V.
What you'll see
No driver-visible symptom recorded.
System reaction
No system-reaction text recorded.
Diagnostic depth
Detection
An incorrect output signal is detected from tachograph pin B7.
Possible cause
An incorrect component may have been connected to pin B7.Fault in the cable harness between the tachograph and the component connected to pin B7.Fault in the tachograph.