Microswitch issue, boot won't open

SansFoy · Post by **SansFoy** » Wed Oct 04, 2023 11:37 pm

Lurking, and now have an issue.

2009 MY. Top began to malfunction, and using a code reader and data streaming, think it is the left side boot closed microswitch. When the boot is down, the right side switch indicates closed, left side open.

Had the boot in service position last night and was checking for bad wiring, etc. It appears the wiring is bad because I jumped the end of the connector and streaming did not indicate the switch closing. I left it unplugged to check for continuity to the CTM as a way to double check it is the wiring and not the switch. As darkness approached, I closed the boot, but window section of roof still on main. This evening, going back to it, the boot will not open, and it is throwing code A690

Not sure what to do at this point. I had thought about trying to drain the battery and see if things reset and quickly open the boot. I have attempted to clear the codes, but A690 returns immediately.

javis20 · Post by **javis20** » Thu Oct 05, 2023 4:35 am

It's the microswitch. https://youtu.be/qcwZC1uah_o

Replacement is easy. Replace both sides.

SansFoy · Post by **SansFoy** » Thu Oct 05, 2023 1:51 pm

Thank you. I was wondering how to get to the switch.

The bigger issue is getting the boot open to get to stuff. Any ideas on that?

Thanks

Chippie · Post by **Chippie** » Thu Oct 05, 2023 4:24 pm

If you have a search there’s a thread on here somewhere showing how to open the boot by jumping some pins in the fuse box.

Chippie · Post by **Chippie** » Thu Oct 05, 2023 4:29 pm

Here you go
viewtopic.php?t=142233

SansFoy · Post by **SansFoy** » Wed Oct 18, 2023 12:14 am

Chippie wrote: ↑Thu Oct 05, 2023 4:29 pm Here you go
viewtopic.php?t=142233

I posted a reply to the below thread, which was the first in this chain
viewtopic.php?t=138150

TL/DR Hit pin 12 with voltage, could hear boot lock activating, boot still won't open

javis20 · Post by **javis20** » Wed Oct 18, 2023 1:11 am

Check out this thread viewtopic.php?p=2026900&hilit=roof+tool#p2026900

Here is the tool. https://www.ecstuning.com/b-genuine-bmw ... 300496598/

Don't know exactly how it works. Apparently you shove it in and push back the rear latch to get the roof into service position. Assume you have to do both sides.

I doubt it's wiring related, 99% sure it's the microswitch. Remember this micro switch is not a passive switch (On / Off). It contains some resistors and there is different resistance values of on and off. So your jumping the plug didn't really test the circuit.

SansFoy · Post by **SansFoy** » Wed Oct 18, 2023 2:47 am

Thank you, but this tool is to release the convertible top from the storage in the boot. My top is current up, but the boot / trunk lid will not open

javis20 · Post by **javis20** » Wed Oct 18, 2023 3:17 am

Well, you've got to put it into service position to get to the micro switch. Why do you need to get in the boot / trunk?

RobbiZ4 · Post by **RobbiZ4** » Thu Oct 19, 2023 8:33 am

SansFoy wrote: ↑Wed Oct 18, 2023 2:47 am Thank you, but this tool is to release the convertible top from the storage in the boot. My top is current up, but the boot / trunk lid will not open

This tool is used to unlock the rear frame with the trunk lid on top so that it can be opened backwards. You can push the hydraulic rams from their locked position to the front. There are small 4mm holes on both sides deep in the black frame structure.
But - the trunk lid has to be opened before to get access to this frame.

The rear brass screw on top of the hydraulic pump has to be released before, max. 2 turns!

javis20 wrote: ↑Wed Oct 18, 2023 3:17 am Why do you need to get in the boot / trunk?

See above.

The microswitches coupling lock have to get replaced, an opened boot is required.

SansFoy · Post by **SansFoy** » Thu Oct 19, 2023 11:05 am

Ok. Tripping pin 12 activated the lock, it still would not open, even with my daughter trying to open it while I jumped it. She then reminded me of the kidnap handle, and I was able to reach through the Ski pass through and pull. Trunk is now open!

That switch was the only fault, so my thought is to plug the new switch in a close it with a rubber band. Then try to cycle the roof to maintenance position and install the new switches. Does my logic hold? Or …. With the switch artificially held closed, will the whole thing stop because the computer thinks the trunk is still closed?

SansFoy · Post by **SansFoy** » Thu Oct 19, 2023 11:41 pm

Update.

Using the kidnap handle, I was able to open the trunk lid and then wired in a new switch. This was enough to trick the system into recognizing the trunk lid was closed and secured. I was then able to push the 'Up' button, and the top finished locking down. All is secure.

However . . . the top will now not go down. When I push the open top button, absolutely nothing happens. No movement or noise. I read the codes, and there are none. The red light on the button is no longer flashing. The trunk opens as it should, and soft-close appears to be working as well

The data stream observations are:
Control button. Open - not operated (when I push the button, the that changes to Operated)
Control button. close - not operated
Cowl panel reached - Yes
Cowl panel unlocked - No
Cowl panel locked - Yes
Roof pack stowed - No
Roof pack erected - Yes
Roof Shell 2 closed. right - Yes
Roof Shell 2 closed.left - Yes
Roof shell 2 stowed - No
Rear-end module open - No
Rear end module closed.left - Yes
Rear-end module closed.right - Yes
Interruption.closing
operation.rear-end - No
Luggage-compartment separation - Closed

What am I missing here?

SansFoy · Post by **SansFoy** » Fri Oct 20, 2023 10:09 pm

Another update.

Updating to hopefully help the next guy.

I pulled the convertible top fuse to see if it was blown. It was not. After putting it back in, and reading the codes again - no codes.

Attempted to top, and it started to cycle. Apparently, cutting power reset it. Now, to get it to service position and replace the switches

RobbiZ4 · Post by **RobbiZ4** » Mon Oct 23, 2023 4:05 pm

When you dismount the right coupling lock system, carefully take out the two hall sensors and check it against traces of rust. Any orange or red point on the housing or a cracked housing are indicators for internal rust, that may disturb the correct function of this sensor.

Examples:

: HS1_NoRust.jpg (88.78 KiB) Viewed 552 times

: HS2_Rust.jpg (75.15 KiB) Viewed 552 times

: HS3_Rust.jpg (108.61 KiB) Viewed 552 times

Even a single orange point on the top line is sufficient to get it replaced with a new one from the E88. And finally don't forget to put a new zip tie around this hydraulic ram, where the former connector was fixed.

Have a look at cracks on these HS housings:

Z4-forum.com

Z4-forum.com