This Pin 12 trick to open the boot

RobbiZ4 · Post by **RobbiZ4** » Mon Dec 18, 2023 7:40 am

At first, the correct parts are the "Hydraulic cylinder, roof shell", partno 54377223333/54377223334
https://www.realoem.com/bmw/en/part?id= ... 4377223333

Problems with these rams, like seen on your videos, might be sourced on one bended piston of this pair of rams. 1/10th of a millimeter leads to a slower speed compared to it's partner.

These parts are very expensive and cost about 720€ each. As you don't have spare parts for testing, it's a very difficult dicision, how to continue.

Normaly exchanging both rams for a first check will show, if this whiggle effect will change to a mirrored behaviour. But, both rams are built constructively a bit different and the left one can't carry the hall sensor, that is mounted into the right ram.

The hydraulic pump has 3 modules: reservoir, hydraulic unit, e-motor. If there is a problem with the hydraulic unit, a motor replacement has no effect on it's (mis)function. What did you replace, the motor or the complete hydraulic pump?

RobbiZ4 · Post by **RobbiZ4** » Mon Dec 18, 2023 7:55 am

B21 wrote: ↑Sat Dec 16, 2023 5:51 pm ...quite a thump when the shells go into the boot too..

That doesn't matter and can be heared very often. To improve this landing sound, you have to replace the two "Gas pressurized springs", partno 54377212634:
https://www.realoem.com/bmw/en/part?id= ... 4377212634
Take new pairs only from STABILUS (0728PB) with 800N, nothing else or cheaper! It's tricky as well, to get it replaced.

B21 · Post by **B21** » Mon Dec 18, 2023 9:56 am

RobbiZ4 wrote: ↑Mon Dec 18, 2023 7:55 am
B21 wrote: ↑Sat Dec 16, 2023 5:51 pm ...quite a thump when the shells go into the boot too..
That doesn't matter and can be heared very often. To improve this landing sound, you have to replace the two "Gas pressurized springs", partno 54377212634:
https://www.realoem.com/bmw/en/part?id= ... 4377212634
Only take new pairs from STABILUS 0728PB with 800N, nothing else or cheaper! It's tricky as well, to get it replaced.

flybobbie · Post by **flybobbie** » Mon Dec 18, 2023 11:41 am

Preempt boot problems, fit a remote boot switch wired back to the boot.
As we know if we get a fail with roof part open, can't open boot.
I can now with remote switch.

Stash36 · Post by **Stash36** » Mon Dec 18, 2023 7:23 pm

RobbiZ4 wrote: ↑Mon Dec 18, 2023 7:40 am
The hydraulic pump has 3 modules: reservoir, hydraulic unit, e-motor. If there is a problem with the hydraulic unit, a motor replacement has no effect on it's (mis)function. What did you replace, the motor or the complete hydraulic pump?

I replaced the whole pump and motor, its looking likely I've bent one of these then. Worth a try if I can get some off a scrapper.
How hard are these to replace, do I need to take the rear shell off? I cant find a video or guide of this anywhere so far.

RobbiZ4 · Post by **RobbiZ4** » Mon Dec 18, 2023 9:10 pm

The rams can be taken off from the lower side of the roof shell. The axle has to be clipped off, then you have to take over the two hydraulic hoses. 2x2 new o-rings are required, 3.3x1.00 mm NBR70.

Used rams from eBay are risky, as they might be damaged as well.
New ones are too expensive to just replace them on a guess base.

Stash36 · Post by **Stash36** » Wed Dec 20, 2023 7:12 pm

O rings ordered, not sure what parts to try. roof motors have them but that's where this saga started.

In addition to the roof, my windows have stopped working, just like trish331 described, and my washer jets are weedy. Think the car is able to read the latest forum problems and provide an instant fault.
We're not getting on at the moment.

Chippie · Post by **Chippie** » Wed Dec 20, 2023 7:20 pm

Is it possible you are discharging the battery

javis20 · Post by **javis20** » Wed Dec 20, 2023 9:09 pm

Are you sure you didn't fry the frm module? Do you have a code reader to see if you can communicate with that module?

That would stop the windows, convertible top and auto headlight leveling. Turn on the car and see if the headlights go thru their start up routine. Left, right and up and down. If they do it's not the frm.

Stash36 · Post by **Stash36** » Thu Dec 21, 2023 7:40 pm

Thanks both.
Battery is fine.
Same as Trish331, my passenger window button works on that side, windows on driver panel dont.
Mirror switches are fine.
Windows drop to open the door, and work ok with the roof open/close mech.

I have a footwell module error, 9CBA disturbed communication with LIN panel / short circuit fault 3.
I was doing a lot of opening and closing as I was removing tints from the windows.

I've read the FRM can lock out, does this make sense to anyone?

If a short circuit is detected in a circuit, the circuit is switched off after ten seconds. This circuit remains switched off until therIe has been a terminal change (terminal 15 > terminal 30 ‐> terminal 15). A renewed attempt to switch on is only made after a terminal change. The control unit permanently switches off the corresponding output if a total of 10 terminal changes have taken place while there is a short circuit in a circuit. After repairing the short circuit, the output is reactivated using a diagnosis command in the testing procedure. If the short circuit is still present, the output will be switched off again after 10 seconds and permanently switched off again after another 10 terminal changes.

B21 · Post by **B21** » Thu Dec 21, 2023 8:06 pm

So the FRM has permanently shut down the circuit after repeated faults..

javis20 · Post by **javis20** » Fri Dec 22, 2023 12:13 am

Sounds like a wiring short circuit or shorted switch. Don't see what it has to do with the hydraulics...

RobbiZ4 · Post by **RobbiZ4** » Fri Dec 22, 2023 8:52 am

javis20 wrote: ↑Fri Dec 22, 2023 12:13 am Don't see what it has to do with the hydraulics...

Indeed, nothing.

Stash36 · Post by **Stash36** » Fri Dec 22, 2023 2:07 pm

I didnt say it did. Just my lovely car bringing me new problems.

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