Roof Shenanigans- E85 2003/08 Production Model

[ann.nonco]

Hi all, hope all is well!

I've recently had some issues with my BMW Z4's roof that hasn't been working of such.
The situation is as follows,

• When the roof is closed - no lights/button pressed no response
  When the roof is manually opened - red light flashing
  When the roof is manually closed - red light flashing then after a while light disappears.

I've manually tried opening it using INPA but it does not work unless(!!) if I manually close the microswitch in the boot.
The metal hook is still there and there is an audible click when the contacts close so physically it looks fine.

When I put an object in the microswitch (closing the contact) strangely pressing close on INPA will fully operate the roof normally and lock it.
I can't seem to close it while the microswitch is manually closed (with the object placed earlier) so when I remove it and open the contact - INPA close function seems to properly close the roof.

All my error codes is just one at AUSSENTEMPERATUR (temp in German) at 12 GRAD C (Celsius).

Would this perhaps be a simple issue of replacing the microswitch and temperature sensor on the car?

Any insight would be greatly appreciated! Thank you.

[markplant]

Does your one touch window function work correctly

[Street]

When I put an object in the microswitch (closing the contact) strangely pressing close on INPA will fully operate the roof normally and lock it.
I can't seem to close it while the microswitch is manually closed (with the object placed earlier) so when I remove it and open the contact - INPA close function seems to properly close the roof.

I’ve reread that many times and I still can’t work it out what works and doesn’t.

You could unscrew the rear micro switch and short the contacts temporarily. That will rule out that as an issue.
Your parcel shelf should be pushing it down so just make sure that’s down or out of the way.

The red flashing lights are just confirming that the hall sensors are registering the roof as not fully open or closed.

Do you never get an amber flashing light?

[enuff_zed]

ann.nonco, are you in the UK?
If so, whereabouts. Maybe one of us could take a look?

[ann.nonco]

Thank you for all your replies!

@markplant
My right side door works fine (both up and down), while my left door opens fully with the one touch function but requires a constant pull to go back up.
As a Japan spec vehicle I was told that this was a safety feature which was also implemented in some other places as well across the world.
My Z4 was Japan spec then it was imported to New Zealand a few years ago.

Many forum posts state that resetting the position/learning/actuation helps with it but I've tried it many times with no avail.

@Street
I'll try that!
When I got the car the parcel shelf was missing entirely so there isn't anything that would be blocking the top's travel down into the boot.
I only get red flashing lights when the top is manually released from lock.
When I fully tighten the roof to close the red lights disappear and no response from the buttons as per usual.

I have never seen a flashing amber light, only seen it hold orange when I press down the button.

I'm planning to check the wiring for the ambient temp sensor as that was being shown on INPA.

@enuff_zed
Thank you for your help!
I'm unfortunately so far away in New Zealand so I unfortunately can't take your offer but thank you so much for your kindness!

Code: Select all

Date:
88/30/23 17:32:06
ECU:
CVM IU
Jobstatus: OKAY
Variant:
CVM IV
RESULT:
2 errors in error memory
18
Bedientaster 'Öffnen' permanent auf GND
Error frequency : 7
Aussentemperatur
sporadischer Fehler
12.00 Grad C
19
Bedientaster 'Schliessen' permanent auf GND
Error frequency: 1
Aussentemperatur
sporadischer. Fehler
SSSSSSSS---
=2222222ニニニニー---
12.00 Grad C

This is the error messages that were present on the Body > Convertible Top ECU.
I do get a proper reading on the dashboard (12 degrees Celsius [It's winter in NZ]) so I suspect it might be something with the wiring.

[Street]

The orange light is the micro switch. Short it as I mentioned above and see how you get on.

You can take the micro switch apart. I’ve had one where the metal arm had been bent and not always making a connection.

[ann.nonco]

A bit of an update,

@Street
The roof operation on INPA only works when I short the microswitch in the boot with an object that closes the metal connection.
With the short the roof closes and opens with only the close soft-top function, never with the open soft-top function at all.

To Open ->
Microswitch shorted, close soft-top function perfectly opens the roof with the windows dropping down.
If microswitch isn't shorted neither open/close works at all in INPA.
Roof buttons do not work.

To Close ->
With the microswitch not shorted close soft-top function perfectly closes the roof with the windows closing once finished.
If microswitch isn't shorted the motor will unlock from the back but the pump will keep asking it to go back down so I need to undo the short.
Roof buttons do not work.

I can also now see an amber/orange light as on the switch on the bottom not the top out of the two.

Would this be a clear tell-tale sign of a bad boot microswitch?

[enuff_zed]

Can we put aside INPA and go back to basics so we can visualise it please.
1. Do you have a parcel shelf, is it fitted properly and is it in the lower position?
2. Sit in the car, roof up, windows up, ignition on.
3. Press the roof down button. What happens?
4. If only the amber light comes on it’s a microswitch issue. Short across the plug which should make the system think it is closed.
5. Repeat 1 to 3. What happens.

Really difficult to diagnose this so please bear with us and go through these steps for now,

[ann.nonco]

Hi @enuff_zed

1. Do you have a parcel shelf, is it fitted properly and is it in the lower position?
2. Sit in the car, roof up, windows up, ignition on.
3. Press the roof down button. What happens?
4. If only the amber light comes on it’s a microswitch issue. Short across the plug which should make the system think it is closed.
5. Repeat 1 to 3. What happens.

1. I don't have a parcel shelf. The boot is empty and there are no obstructions.
2. N/A
3. No light comes up and there are no noises.
4. Shorting the microswitch in the boot still makes no difference.
5. No improvements unfortunately after repeated attempts.

[ann.nonco]

Hi All,
I've done some troubleshooting just to follow up my previous reply and I suspect that it might be a wiring loom issue for the moment.

https://zroadster.org/threads/z4-e85-ro ... xed.39549/
viewtopic.php?t=135077

I've found these two similar articles, especially the first one being very close to my situation with the same exact error messages although I don't have the GapTech module.

I'll be doing some further investigation but after removing the headliner plastic the wires up until the hinge it looked good (even after cutting open the protective sleeve) so I'll probably have to look deeper into the whole harness.

[enuff_zed]

Hi @enuff_zed

1. Do you have a parcel shelf, is it fitted properly and is it in the lower position?
2. Sit in the car, roof up, windows up, ignition on.
3. Press the roof down button. What happens?
4. If only the amber light comes on it’s a microswitch issue. Short across the plug which should make the system think it is closed.
5. Repeat 1 to 3. What happens.

1. I don't have a parcel shelf. The boot is empty and there are no obstructions.
2. N/A
3. No light comes up and there are no noises.
4. Shorting the microswitch in the boot still makes no difference.
5. No improvements unfortunately after repeated attempts.

OK, and you've already done the window reset so that shouldn't affect it.
You could try with the windows both down, just in case?
If you have no parcel shelf then you definitely need to bypass that micro-switch permanently of course.
It is unlikely that both relays have failed or all three fuses blown, though worth checking them anyway.
So we're left with either the control module or a wiring fault in the roof loom.
bigwinn is the knowledgeable one regarding the roof loom. Stuart, would you expect nothing at all, or would the front still unlock?

The control module sits behind the LH seat, hidden behind the square grille in the outer trim panel. I'm guessing it won't be easy for you to source a replacement, unless you can find another owner willing to let you do a diagnostic swap?

[bigwinn]

Hi @enuff_zed

1. Do you have a parcel shelf, is it fitted properly and is it in the lower position?
2. Sit in the car, roof up, windows up, ignition on.
3. Press the roof down button. What happens?
4. If only the amber light comes on it’s a microswitch issue. Short across the plug which should make the system think it is closed.
5. Repeat 1 to 3. What happens.

1. I don't have a parcel shelf. The boot is empty and there are no obstructions.
2. N/A
3. No light comes up and there are no noises.
4. Shorting the microswitch in the boot still makes no difference.
5. No improvements unfortunately after repeated attempts.

OK, and you've already done the window reset so that shouldn't affect it.
You could try with the windows both down, just in case?
If you have no parcel shelf then you definitely need to bypass that micro-switch permanently of course.
It is unlikely that both relays have failed or all three fuses blown, though worth checking them anyway.
So we're left with either the control module or a wiring fault in the roof loom.
bigwinn is the knowledgeable one regarding the roof loom. Stuart, would you expect nothing at all, or would the front still unlock?

The control module sits behind the LH seat, hidden behind the square grille in the outer trim panel. I'm guessing it won't be easy for you to source a replacement, unless you can find another owner willing to let you do a diagnostic swap?

Hard to say as all the loom issues I’ve had have been mid cycle- not opening or closing- I guess due to the majority of movement on the loom at that point

[spazmochad]

The loom by the window is a weak point, I'd check the wires there first. One of mine had snapped and required fixing, there's a mesh wrap you have to cut in order to see the individual wires.

[ann.nonco]

Hi all,

OK, and you've already done the window reset so that shouldn't affect it.
You could try with the windows both down, just in case?
If you have no parcel shelf then you definitely need to bypass that micro-switch permanently of course.
It is unlikely that both relays have failed or all three fuses blown, though worth checking them anyway.
So we're left with either the control module or a wiring fault in the roof loom.
bigwinn is the knowledgeable one regarding the roof loom. Stuart, would you expect nothing at all, or would the front still unlock?

I've tried it with the windows down and it makes no difference.
Thank you for the microswitch tip!
Relays are all okay after testing it with a multimeter and all fuses are OK.

Control Module seems to be fine as INPA and ISTA-P seem to communicate it without issue but the error messages (temp ground) really seems to be a loom issue at this point.

Does anyone have any tips on removing the whole loom?
I can't seem to get access down into the module as once the loom passes through the most bottom hinge even removing the LH seat rear trim it's still inaccessible unless maybe if I remove the roof entirely.

The loom from the locking motor until the hinge is fine after removing the mesh front to back - there are no bends or cuts from what I see so maybe it's even further down.

[ann.nonco]

Okay so an update for the Z4 under question, I think that my Z4 might be haunted with electrical gremlins right now.
I haven't had time to check the full wiring loom but currently the roof does not open at all using INPA. Not due to low battery voltage as it's constantly on a tender.

I was driving on the highway today when suddenly at 80km/h the roof decided to open by itself (latch and pump activated - sound and operation confirmation) then with the roof opened the latch proceeded to constantly lock and unlock randomly. I think the wire short has become more serious so I need to have a look into the whole thing, for the meantime the latch motor has been disconnected so it should stop moving around.

The hydraulic pump bowden cable release does not work so I need to replace that, same as the stowage lock release cable is somewhat overextended so I think that has failed as well. When I pull both cables they don't do anything.

I've taken apart the front console that houses the up/down roof buttons but they all seem fine without any bends so I think it might be somewhere near the passenger b pillar (Japan spec so it's RHD) where all the modules and connections congregate. The buttons flash UP RED constantly so it still thinks it's up when I've manually locked it in place.
Need to source a new wiring loom but before that maybe take the roof out entirely and have a look at all the wiring connections as INPA reports the OPEN button is constantly reporting it's being pressed on. 

Otherwise the car itself is fine, need to get some coilovers and new bushings. It's still a blast to drive so I'm happy.