Convertible top control module dead?

[Briancampbell604]

2003 new to me z4 3.0i .
I have seen mention of several top problems and solutions, but I haven’t seen mine mentioned. My issue is the orange top light is always flashing and doesn’t change from flashing no matter what . I have checked all fuses and verified voltage and ground at the module. I tried two of my friends scanners ( snap on modus ? And snap on Zeus) both say no communication with the module . Am I correct to assume the module is bad ?

 

[tug]

Is the light red or orange? If its orange then it will be the shelf sensor. If red then yes, there is another problem.

Cheers, tug

 

[enuff_zed]

Sounds a bit odd though as usually the orange light only flashes while you’re trying to operate the roof?
Definitely confirm the colour first.
If there’s no communication with the module though that does sound a bit like it could be the issue.
Modules are easy enough to change. Whereabouts are you? Maybe someone nearby with a spare you could swap to check

 

[Briancampbell604]

Bottom orange light (I think the top light is the red one ?) , just blinks like a steady heartbeat it blinks even when the car is off and locked . I’m in Alabama , US .

 

[enuff_zed]

Bottom orange light (I think the top light is the red one ?) , just blinks like a steady heartbeat it blinks even when the car is off and locked . I’m in Alabama , US .

No worries, simply provide an air ticket and some beer and I’ll bring one over.
On a serious note, that points to the module for me

 

[Briancampbell604]

That’s what I was thinking, I even took the board out of the casing under magnification to see it I could see anything obvious. The modules are very expensive at least .

 

[enuff_zed]

That’s what I was thinking, I even took the board out of the casing under magnification to see it I could see anything obvious. The modules are very expensive at least .

Do you mean 'NOT' very expensive?
Easy to come by in the UK.

 

[Briancampbell604]

Lol I meant to say not very expensive.

 

[enuff_zed]

Lol I meant to say not very expensive.

Never quite know with the prices over there. Well I hope it fixes it for you.
And on the bright side, it helped you find the best forum on the interweb.

 

[Briancampbell604]

Honestly if the front hooks would unlatch and latch when I press the button I probably wouldn’t even bother digging any deeper . Turning that part manually takes a while .

 

[Briancampbell604]

Hopefully find one to order on eBay soon .

 

[Briancampbell604]

Update : I received my eBay top module and my cowl latches work now . I can hear the actual top motor running but it doesn’t move the top , I think the manual bypass is stuck in bypass . I will try to take the motor out of the side bin to check it tomorrow.

 

[enuff_zed]

Update : I received my eBay top module and my cowl latches work now . I can hear the actual top motor running but it doesn’t move the top , I think the manual bypass is stuck in bypass . I will try to take the motor out of the side bin to check it tomorrow.

One step forward. That’s good.
I assume you’ll relocate the motor into the trunk then?
When you disconnect the manual lever assembly from the pump head you’ll see the small brass plunger. It has a small hex head and sometimes you can free it off by oiling and twisting. If that fails there is a blank on the opposite side. Take that out and use a thin pin punch or similar to push the plunger back out.
Have plenty of rags to stop the oil getting into the carpet if you go this way.
In the trunk location the pump will be at a greater angle. To prevent the ports being uncovered and sucking air, top it up with hydraulic jack oil until it spills out the top. This will still leave an adequate air gap when you tilt it back but is enough to ensure it works properly.
You may need to assist the movement a couple of times until it self bleeds. Then check the level again.
Don’t secure it in place until you’re sure it’s working properly.

 

[Briancampbell604]

Thank for the tip, Definitely going to relocate the motor . On another note before I replaced the module the AM/FM radio reception was zero and now its perfect , I didn't see anything that would have that effect in the top module but I will take all the help I can get from things fixing themselves .

 

[zriha]

The main problem from my experience now dealing with Z4 and roof is that besides relocating the motor (if it is rust, then it will die), and shelf sensor that can break easily.

In the case of the shelf sensor - the orange light will always on - light will be on if you try to operate the roof.

But, if the orange light is blinking, from the moment you started the car, and nothing happens when you press the button to operate the roof, then the problem is usually in the wiring.

Here is what it looks like:


After 10+ years of the roof going up and down, this cable:


have serious breaks in the wires. I had so many problems with that, that I ordered a new set of cables hopefully it will work like a charm for another 20 years.

Wiring can easily break, it is not the case with Z4, but also BMW 3 series of that generation.

 

[Briancampbell604]

I tested continuity of the wires I could easily access including the shelf switch before I ordered the module . I also checked the system with two snap-on scanners and neither one could access the module . At that point it was worth the gamble to order the module ( $80 ) . After the module was put in everything functioned except the actual top moving (but I can hear the motor running) . The manual release doesn't feel like it is reengaging . I want to relocate the motor anyway so when I pull it out I can check the bypass .

 

[zriha]

Are you certain to rule out the wiring?

What I had as a problem:
a. First started as a normal top operation, but occasionally, when I would close my top, it would stuck at a certain point - sometimes halfway up, sometimes almost closed, or opened.
b. I would put my fingers direct above me, and I would dangle the wires, sometimes, the trick would be enough, and the procedure would just continue.
c. Now, the cables are fully broken, and the red light for closing the top is flashing all the time, and I mean all the time. I bought new wiring, but I am waiting for good weather to take my car to BMW specialist as changing wires for yourself could be a nightmare.


I tried to do it myself, but then we got like weeks and weeks of bad weather, and you need to seriously disassemble the top.

 

[enuff_zed]

I tested continuity of the wires I could easily access including the shelf switch before I ordered the module . I also checked the system with two snap-on scanners and neither one could access the module . At that point it was worth the gamble to order the module ( $80 ) . After the module was put in everything functioned except the actual top moving (but I can hear the motor running) . The manual release doesn't feel like it is reengaging . I want to relocate the motor anyway so when I pull it out I can check the bypass .

That sounds exactly like what you seem to suspect.
The red handle has been pulled and the bypass plunger pushed in; and that is where it has stuck. The motor is busy churning hydraulic fluid round the pump but it's not going to the rams.
Once you get it into the boot (trunk) you can remove the plastic bracket holding the lever and you'll see the brass plunger. It only moves about 3-4mm if that. You can get a 5mm socket on it and keep turning it, with a little oil on it to help, and it should soon free up.
If not, then on the opposite side of the pump head is a blank. Unscrew this and you can get a pin punch or similar onto the rear of the plunger and push it back out.

 

[Briancampbell604]

Update : I replaced the module and after that the top would unlatch , definitely had a bad module. Then I pulled the top motor out and it was out of fluid so the bypass wasn’t stuck it just didn’t have fluid to cause resistance. I put fluid in and it will cycle several times until it runs out of fluid . I plan to take the whole top off and inspect the lines and connections.

 

[enuff_zed]

Update : I replaced the module and after that the top would unlatch , definitely had a bad module. Then I pulled the top motor out and it was out of fluid so the bypass wasn’t stuck it just didn’t have fluid to cause resistance. I put fluid in and it will cycle several times until it runs out of fluid . I plan to take the whole top off and inspect the lines and connections.

Hydraulic line leaking then.
See if you can determine which side as then you can get away with only lifting that side of the roof rather than completely removing it.
Could be any of the lines but the main culprit is the 90 degree bend at the bottom of the ram, as if the drains are blocked it gets wet and corrodes through.