Hard top sensor bypass

[gaj5675]

I had a power hard top malfunction and the dealer wanted $5000 to replace a wiring harness and sensor. I am finding a specialty shop outside the dealer but until then I cannot put the windows up and the dealer would not do anything about that for a $400 diagnostic charge. The middle section will not lock into place and car recognizes malfunction and will not let windows go up.

Is there a way to bypass sensors at least once to get the windows up?

2013 Z4 E89 s28i

[bigendbob]

Do you know which sensor from diagnostic check.
Quite common are wire breaks in the harness visible from inside the cabin on the right just behind headrest as you look right.
Poke around there you might just reconnect break and cycle might continue.
This was my cars fault:
https://z4-forum.com/forum/viewtopic.php?f=45&t=127188
Many other fixes on forum.

[surfwooder]

I'm interested in possibly helping you with this roof problem. I do have a few questions for you. 1st, what have you done so far? Have you looked at any sensors, either Hall, or micro switch? Did you ask the dealer why they wanted to change the entire wiring harness? Did they find many broken wires, just one? The windows up/down signal travels to the Convertible Top Module (CTM) via the "K-Can" system. The CTM will evaluate other events before it will allow the windows to move either up/down. The Footwell Module (FRM) is a major player activating the front side window regulators, in order to open the top. The Junction Box Electronics (JBE) actuates the rear power window regulators. The back side windows must be lowered for the top to be lowered. The JBE sends a indicating whether the truck lid is closed. The JBE also provides the CTM with 30a. The Car Access System (CAS) is the master control unit for the power window regulators. You may want to check your ambient temperature display, since if this sensor shows out of range operation temps, the CTM will stop all operations. I hope this helps.

[surfwooder]

Oh, by the way. You mention the "middle section" of the top. Do you mean the section that latches to the top of the wind shield? This is where the drive for the locking system is located. There are two Hall sensors, which sense the panel as it approches the windshield. The Hall sensors allow the right and left claws to clamp to the windshield, and micro switches detect when the claws are in place. All 4 of these sensors send signals to the CTM.

[RobbiZ4]

Originally Posted by surfwooder

...There are two Hall sensors, which sense the panel as it approches the windshield. The Hall sensors allow the right and left claws to clamp to the windshield, and micro switches detect when the claws are in place. All 4 of these sensors send signals to the CTM.

To be honest, this is not correct.




There are 2 microswitches next to the front locking motor inside of the front panel. In addition, one microswitch on top of the windshield on the passengers side (UK: drivers side).