Convertible top not working

[jgood1020]

Hi everyone, I have a 2003 Z4 2.5i and am having issues with the convertible top not working. Below is a brief summary of what's going on and things I've checked:

1) Both the red and the amber/yellow lights near the convertible switch buttons are flashing in unison, even when the engine is off and the key is out.

2) No movement or noise when I use the roof up/down buttons from either the open or closed position. The locking motor doesn't engage, the roof motor doesn't make a sound, and the windows don't move. The windows do move down a bit when opening/closing the doors, which I know is normal.

3) Pulling the red tab in the trunk doesn't seem to make a difference in moving the roof manually. I can open/close the roof by hand with the tab in either position.

4) The top doesn't seem to be clicking into place when I manually open it. It just rests down in the roof compartment. The center console button doesn't seem to be catching.

5) I've removed the micro switch from the trunk and jumped the wires together, but the amber/yellow light is still blinking.

6) I received the car from a family member who mentioned the roof was working normally around a year ago.

7) I don't have a scanner right now so I'm not sure which, if any, codes are being thrown. Ordered a new scanner and should have it next week.

8) The windshield frame cover was damaged when I got the car, causing the roof to sag near the front. I'm wondering if this might have damaged the hall sensors in the front of the roof. I ordered a new frame cover which should hopefully be here next week.

I've gone through multiple forums and read a number of DIYs, but I haven't really come across the situation I'm in with both lights blinking constantly. Any help or insight is greatly appreciated!

[JAS1169]

Before doing anything, try resetting your windows, they are linked into the top's operation. Please see attached:

E85 roof not activating (no lights, no motor noise) (zpost.com)

[jgood1020]

Thanks for the link to reset the windows. I tried both ways for resetting and unfortunately it didn't help the convertible issue. When I manually close the top and have the windows rolled up, both sides will drop 1" or so when I open each door, so it seems like that part of the window function is working. However when the roof is closed and I press the roof down button, the windows don't move and I don't hear any noise or see any movement from either the locking motor or the roof motor.

Both the red and yellow LED lights near the convertible switch buttons are blinking in unison, which I haven't run across in any threads. The scanner I ordered should be in tomorrow so I'm hoping that sheds some light on what is going on. Appreciate any additional help or suggestions!

[JAS1169]

Yea, get a scan of your system and hope your new scanner is detailed to read roof errors.

When pressing roof down, does the system start and releases the roof from the windshield frame...or...do you have to manually release the roof with an Allen wrench? When closing to you manually bring the top up and then press close and it will it lock up....or...again need a Allen wrench?

[jgood1020]

When the roof is closed I have to use the allen wrench to manually unlock the roof hooks then I have to open the roof by hand and set it down in the compartment. When the roof is open, same thing just in reverse: I have to manually lift out the convertible top from the compartment then hold it close to the windshield frame while turning the allen wrench to lock the roof hooks. I've tried pushing the roof open/close buttons in a bunch of combinations between the roof being locked/unlocked and in various positions (closed, open, half-way), yet nothing seems to get a reaction. The lights keep blinking and I don't hear any motor noise or see any movement.

I've found it kind of strange that the yellow LED light near the switches blinks constantly. I've read that the yellow light will come on when the shelf in the trunk isn't down (I have it down and I've bypassed the micro switch with a jumper, so don't think that's causing the issue), but I haven't seen where the light will blink. I know the red light will blink when the roof is stopped somewhere between open and closed. Wondering what a yellow blinking light means.

[JAS1169]

Based on the info you've provided I'd strongly suspect the convertible controller is not able to communicate with the motor in the front of the roof which releases the roof from the windshield.

I don't know the damage incurred to the windshield frame or....if this also caused unseen damage to roofs frame which is causing it to sag. This roof sag (# 4 of your original post) might have caused issues with the contact points for the front hall sensor.

However, there is a wiring harness between the roof and liner which connects the hall sensors to convertible controller which might have a broken wire/bad contact.

However, if the convertible controller loses contact with a hall sensor, it basically shuts down the system because the controller no longer knowns the location of the roof.

I honestly wouldn't do anything further until you put a code reader on it which has the ability to pick up roof errors. This hopefully will give you a good starting point.

[jgood1020]

Thanks for the info, I suspected a connection issue somewhere between the controller and motor as well so it's good to hear someone else think that might be the problem. I'll update this thread with any codes from the scanner hopefully this weekend. Appreciate your help so far!

[jgood1020]

So my scanner came in (Schwaben NT510Elite, the BMW specific one) and it's able to see a number of control modules, however the convertible top module appears to be missing. I went through all the settings and was able to see live data and codes regarding modules for other control systems (DCS, door locking, steering angle, etc) but information about the soft top didn't show up anywhere. The module was missing from the main list of control modules and nowhere else did it show status info on micro switch, convertible top position, Hall sensors, or anything. This leads me to believe that it's either a wiring problem to/from the convertible top module or the module itself has failed. I think this disconnect might also explain why the convertible top switch lights are both constantly blinking.

Do you have any tips on how to begin diagnosing faulty wiring or a dead control module?

[JAS1169]

I went to the site for your NT510/bmw and went over what it could allegedly do Bmw_en - Google Sheets and it claims it does do the convertible controller. I would double check by contacting schwaben (email) and tell them what's happening and you've got zero for convertible controller & ask what does this mean? There explanation as to why this system isn't coming up on your reader might be your best bet for your next step.

Ok, given all your facts you could try a fresh restart of the whole system by pulling a cable off the battery and then waiting 20 mim and then reinstalling the cable. This should refresh your computer system. However, you should be aware that by doing this your car might go into transportation mode. The transportation mode has happen to a few who have installed new batteries.

[jgood1020]

I went with my gut and bought a used convertible control module (CVM) off eBay, and lo and behold when I connected the new CVM the blinking lights stopped! I put the convertible in the closed position and manually locked it, then hit the roof open button and the locking motor worked to unlock the roof. However, once the roof was unlocked it didn't continue to open. I heard the hydraulic roof motor running, so I think what happened is that the red pull tab (bowden cable) in the trunk was pulled too hard and jammed the hydraulic bypass valve open. I think this is the culprit because regardless of where the red pull tab is (inserted or pulled out/rotated) I'm able to open/close the roof manually with no hydraulic resistance. My next step will be to try adjusting the bowden cable, and if that doesn't work I'll be taking the top off to get to the hydraulic motor to inspect the bypass valve connection.

[JAS1169]

You got lucky, you should play the lotto, you might be on a roll. I hope you understand that I wouldn't have recommend your action only because it could have resulted in you spending $$$ on something that potentially might not be a issue.

Yes, your bypass valve is jammed at the pump. Generally, playing with the cable is a waste of time....but, you might still be on a roll. The valve itself is jammed at a brass ball bearing which has a spring behind it. White crude has built up around the bearing locking the bearing into the open position. (The white scum is believed to be soap from washing the car which over time leached into the black casing.) You have to reach the motor/pump remove the Bowden cable harness, which will give you access to the jammed bearing, then spray wd-40 on the bearing and work it (push in out) until it releases.

You can either pull the top or attempt the thru the trunk method to reach the pump. However, the only thing I would strongly recommend is at the end to have the motor/pump relocated to the trunk.

[JAS1169]

I should note, that although in all likelihood your bypass is jammed open, there is the potential for either failed hinge lifters or a blown line. However, your next step remains the same; reaching the motor/pump.