Roof Won't Lock

[TonTon333]

I recently purchased a Z4 that has a myriad of problems but the biggest being I can't put my convertible top up so I'm driving around with jacket and gloves looking like a goober.

Turning the allen key on the top motor only makes the screw come out instead of spinning the lock cables. I took the motor out and it has the typical cracked plastic gear but that should only affect the power coming from the motor itself (and all I want to do is manually close with an allen key). With the motor pulled out and I turn the allen key it spins the little nubs that turn the wire cable just fine. Once I put even a moderate amount of pressure onto them then they don't spin and the screw starts coming out (as I think it should since any force put on the screwing motion would pull it out.

I think my TLDR problem is why is there so much resistance turning the cables that are supposed to lock the latches on the roof. I tried even turning them without the motor attached using a wrench and they won't budge. I attached pictures of my motor and one cable attached to a nub so people get an idea of what I'm talking about but I think the broken motor is irrelevant to my problem.

 

[skelters]

Never heard of any of these failing before or I've missed the posts!

Think this might be the part...
£64.99 on the FleaBay....
https://www.ebay.co.uk/itm/BMW-Z4-E...016798?hash=item3d7f7eba9e:g:I1QAAOSw11BcOSey

 

[TonTon333]

Yea it sucks that I'd have to buy the whole motor when just the plastic gear is broke. However I don't even necessarily want a new motor or gear. I'm just trying to turn the part the motor turns on my own (same as how turning the allen key would do, motor vs spindle is just two different methods of spinning those grey/black spindles when then spin the locking hooks shut).

My manual override system for locking the top is broken so its impossible to lock.

 

[srhutch]

Could the fault be on the manual side of the motor though, which is why that cog broke.

If the motor couldn’t spin due to an issue with the cables or motor assembly then the weakest part has failed.

I’d get another roof motor, you need to anyway and see where that gets you.

It broke for a reason, and I’ve never seen one break.

 

[TonTon333]

Well if the motor encountering resistance with the cables after the motor is what broke the gear, wouldn't it just break it again once you put a new motor in? In theory it doesn't matter if its that plastic gear or myself spinning the screw in the middle, it should then be transferring the power to the cables and locking the roof to the windshield.

I'm wondering maybe if there's some kind of state or sensor that the latches need to be getting an electrical signal from before they allow opening/closing (don't know if they have any electronics going to them or if its all just mechanical from the cable). I would think not because bmw made a manual override method in the first place where you just have to turn that screw with an allen key without pushing any buttons to latch/unlatch.

 

[srhutch]

In theory it doesn't matter if its that plastic gear or myself spinning the screw in the middle, it should then be transferring the power to the cables and locking the roof to the windshield.

It matters if the issue is on the other side of the broken cog to the motor, which is why you probably cannot turn it.

Have you tried doing it without the roof closed so that there is no resistance with the catches?

 

[TonTon333]

To clarify, I can turn the center screw with an allen key while the motor is out of the car and the spindles/cables turn along with it. So i dont think its any resistance from the motor itself. Its just when the cables attached to the locks.

Also yea I was trying with the roof top as far down as I can pull it while also trying to turn the allen key or cables by hand. Not sure if theres any other mechanism that would stop the latches from moving. Not thrilled about it but I might go so far as to keep dissasembling until I remove the latches themselves and learn how they work.

 

[Number5]

Id guess its the sensor on the passenger side front hook has slipped and therefore the roof ECU isn't getting the message to stop winding when its at the stop point.

You'll need to peel the canvass back off the front of the roof, remove the foam filler pad and check the sensor hasnt slipped over the stop point.

 

[TonTon333]

Sorry didnt get a chance to look at it until now. I attached pics of what I'm seeing. There are wires going to a "hall sensor" on the drivers side and the only wire going towards passenger seems to be just for knowing when the roof is locked in the down position.

Also I removed the plastic cover and sound deadening but theres another thick metal part over the hooks themselves that I assume I need to somehow get off.

 

[DrewsE85]

You ever get this fixed TonTon333?

 

[Z4USAVA]

To all Z4 owners with a Flashing Red Light on the control panel...............

BMW convertible roofs on the 2004-2008 Z4 are complex in design and function. I have spent over a year rebuilding the roof on our 2004 Z4 2.5. The last issue I have faced was a fully operational roof that would not lock at the front cowl by the windshield or unlock in the back when collasped. The cowl should automatically unlock in the back when closing the roof (of course you can manually unlock the cowl in the back). My problem was the two roof locks (Part# 54347043873/left and Part# 54347043874/right) in the compartment underneath the roof canvas near the windshield. The hooks on the locks (which secure/lock the roof to the windshield frame) need to fully collasped to a L-shape in order for the roof to be fully secured and locked. The hooks on our Z4 would collaspe partially resulting in a flashing red light on the panel and an unsecured roof. The solution was replacing the locks and adjusting the hooks. Problem solved.....