Manual activation of retarder
â–¶ How to fix
Check the retarder lever or the retarder-Opticruise lever including wiring and connectors.
What you'll see
No driver-visible symptom recorded.
System reaction
No system-reaction text recorded.
Diagnostic depth
Detection
The voltage in the retarder lever circuit or retarder Opticruise lever circuit has been either above or below the permitted level.
Possible cause
Short circuit or open circuit. There may also be a fault in the retarder lever or the retarder-Opticruise lever.