Vehicle: 2003 BMW Z4 Roadster (E85), L6-3.0L (M54), Automatic Transmission

Mileage: 192,557

Problem: The vehicle was in the shop to fix an inoperative convertible top issue.

Details: A system-wide scan showed no convertible top diagnostic trouble codes were present. Next, the technician inspected the convertible top’s hydraulic top system. He found the system was almost empty due to leaking hydraulic cylinders. After replacing the cylinders, the top still didn’t operate. At this point, the tech called ALLDATA Tech-Assist for some assistance.

The Tech-Assist consultant noted that this system uses Hall switches with triggers to control operation. He suggested testing the Hall switches by using a scan tool to look for any abnormal convertible top switch “states” (Example: OPEN when it should read CLOSED)

By moving a flat-blade screwdriver in front of the Hall switches, the tech was able to see if they were working correctly. All the switches registered on the scan tool, but the tech noticed that one switch was missing a trigger. It was supposed to be bolted to the convertible top frame. After searching around in the trunk, he found the trigger.

Confirmed Repair: The tech installed the trigger and the convertible top began working normally. Fixed!