Button lighting malfunctioning

Read the instructions below then start the fault diagnostic procedure.

Symptom: Button lighting malfunctioning

Button lighting malfunctioning

Fault symptoms

Button lighting malfunctioning

Diagnostic help

Check whether the interior lighting is working. If not: check fuse 4 in the cabin.

The following values can be read with the diagnostic tool:

-	Rheostat Filtered

-	Rheostat Night Panel Filtered

-	Night Panel (Bus from SID)

The following functions can be activated with the diagnostic tool:

-	Button and control illumination PWM output

Check the wiring harness

Jiggle the wiring harness in several places and in various directions to detect intermittent open circuits and short circuits in the wiring harness. Watch the multimeter, diagnostic tool and test lamp during the check.

Measures