On some 7 Series, 5 Series and X5 models, including the 2001 M5 5.0L, the charge warning circuit in the instrument cluster can fail, causing the charge warning indicator to be illuminated at all times. If the instrument cluster is replaced, the same failure recurs.
The cause is that the coupling capacitor on the ignition coils is not grounded, leading to a voltage backfeed and resulting in damage to the instrument cluster. To avoid a repeat failure, before installing a replacement instrument cluster, check that the ground lead is properly attached to the grounding stud.
Courtesy of IDENTIFIX.
For more information, visit www.identifix.com.