The next day, Jack decided to investigate further. He used a multimeter to measure the voltage at the IKE module and discovered that there was a strange voltage reading on one of the pins. He suspected that there might be a short circuit somewhere in the wiring harness.
After pouring over the diagrams, Jack noticed that the wiper circuit was connected to the Instrument Cluster Module (IKE), which was also responsible for controlling the dashboard instruments. He suspected that the problem might be related to a faulty IKE module or a short circuit in the wiring.
With the problem identified, Jack was able to repair the wiring harness and replace the faulty IKE module. The car's electrical system was back to normal, and the owner was relieved to have his car back on the road.
Jack knew that the E39's electrical system was notorious for being complex, with multiple control modules and a Can Bus network that connected them all. He decided to start by checking the wiring diagrams and schematics for the car's electrical system.
As he was inspecting the dashboard, he noticed that the instrument cluster was malfunctioning, and the wipers were moving on their own. The car's owner had mentioned that the problem started after a recent visit to a local mechanic, who had attempted to repair a faulty air conditioning system.
After a few hours of searching, Jack finally found the problem. A faulty wiring harness had been installed by the previous mechanic, causing a short circuit that was affecting the IKE module and the wiper circuit.