intermittent roof problems

thee89

Member
So I got this car in september of 2021, its an 09 30i, and in the winter I had faced an issue where my all of windows would go down, and then i got the red flashing light and my windows would not work and my trunk would not open, the hard top was latched because obviously i hadn’t lowered it in the winter. I went to bmw and they reset it and got me my trunk open and it stopped for a little. then there was a long period of time where all the windows were up, the light was flashing red at me, and i could not put my windows up and i had the constant signal. when it warmed up, i was able to just put the whole top down and then put it back up and it was fine. i didn’t have any issues until yesterday i had driven somewhere with my top down, and i began closing it but it got stuck halfway. i have a shitty scanner so it’s not throwing any codes that i can read, and i can’t really take it to the dealership with it the way it is right now. i’ve torn apart the trunk and located the microswitches and the hall sensors. how do i check the hall sensors that are mounted on the hydraulic pumps? or any advice in general? this is my daily so it would be greatly appreciated
 
Hello and welcome to the forum
Have a look through this thread
https://z4-forum.com/forum/viewtopic.php?t=130855
 
It sounds familiar to me.
My rear window panel stopped half closed yesterday.
Straight away i know it will be a broken wire as i have fixed two already.
Warm days finally trigger the faults, probably things expand just enough for wires to touch randomly.
In my case a code came up (Hall sensor roof shell 2 packed) , so i know where to start looking.

I did some years ago drop the windows and roof wouldn't move.
That was a bad connection under the switch panel in the drivers door.
Just needed pulling cleaning and refitting.
That problem might not throw a code.
But that started with random inability to drop drivers window.
 
Read this at first:
⌛E89: Retractable Hardtop (roof) Maintenance
https://z4-forum.com/forum/viewtopic.php?t=130932


thee89 said:
... but it got stuck halfway. i have a sh***y scanner so it’s not throwing any codes that i can read,
Your scanner is not s**t.... For many roof faults no codes are stored.

thee89 said:
... and i can’t really take it to the dealership with it the way it is right now.
Driving very slowly is an option for some 10 miles. But, do you have an Indy with E89 roof experience next to you? There are some garage recommendations available in this forum.

thee89 said:
.. and located the microswitches and the hall sensors.
Don't think that you will find their exact locations.

thee89 said:
how do i check the hall sensors that are mounted on the hydraulic pumps?
That's a problem, as you don't have any idea how this roof machine works:
There is only 1 hydraulic pump (not pumps), there are 6 hydraulic rams, there are 12 hydraulic hoses, there are 5 hall sensors mostly mounted ON the rams, there are 6 microswitches mounted anywhere, there are dozens of wires of which 6 are candidates to crack after 8-10 years.
All this stuff to locate, to check or to repair while the roof doesn't work anymore is impossible for you except you are Jesus. :driving:

At first, get the two salmon relays replaced next to the hydraulic pump below the trunk's floor. Even if it's complicated in the current situation, it might be an option.
 
Friend of OP here: We began to pull the hoses from the pump in an attempt to remove whatever possible so we can open the metal cover on the pump motor to see if the pump has been damaged due to relay failure or otherwise. We lost a small amount of fluid on the first hose (upper hose, closest to the rear bumper), and the the second hose we disconnected started spraying fluid, not realizing the system was still pressurized. we reinserted both hoses and bolted them down and did a little cleanup. We've now done a single half turn on the pump depressurizing bolt (closest to the battery) and lifted the two top panels up to the windshield, then screwed the depressurizing bolt back tight. Is it okay to pull the motor cover off the pump without taking any of the hoses out? We have unplugged quite a few electrical connectors to make things easier. Did we do any permanent damage so far? We heard some hissing when moving the top after depressurizing, and later read that the o-rings on the hoses are considered destroyed once they've been dismantled. Does anyone have specs on those o-rings? How can we test if the CTM is operating properly? Is there a way to lower the panel that the boot lid is connected to? Let us know if there are any other pictures that could be helpful.

Thanks,
Evan J
 
We read through a lot of Robbi's material on zroadster and others, and determined with an unknown relay life, the pump could be a major concern. What steps would you go through instead?
 
I have a third roof problem occur last week.
Rear shell stopped half way. Code reader says faulty sensor but i know it will be a broken wire.
Monday project is to just splice in all new wires from sensors to boot.

Perhaps a cheap obd reader not programmed to detect roof problems.
I use a Foxwell NT520pro with BMW specific software added and is a frustration saver.
It has told me pretty much where to look, sensors or salmon relay.
Then cheapo multimeter to check continuity of each cable.
Circuit diagram with cable colours useful.
See here; https://z4-forum.com/forum/viewtopic.php?t=119914

Attacking the pump i don't think is your problem.
If the computer doesn't know the status of windows the roof won't operate.
I don't think anyone has had a pump failure other than flooding.

What it looks like to me is the binding tape is sticky and it looks like it made the insulation brittle.
It shrinks and splits so the copper inside has no support. Finally it breaks just enough to be intermittent.
On warm days the problem seems to show when everything expands.
 
If you dump the hydraulic pressure, boot lid needs to be propped up.
Then i place a cardboard box between the hoops and lift the rear glass section over to box.
That way i can get at all the wiring.
Then remove the the roof liner, just wedge hand in gap and it pushes away.
 
wetpee said:
We read through a lot of Robbi's material on zroadster and others, ...

I've never ever written anything about removing the hydraulic hoses from the pump!

Turning the brass valves while beeing under pressure may destroy it's internal o-ring. Very critical next to suicide.

The top cover of the pumps motor can be pulled off without dismanteling anything. Opening 2 screws on the right, then pull the metal cover. No oil leaking will happen.

BUT - this step makes only sense, if there is massive corrosion visible BELOW the pumps motor.

Opening the pump is the last step after several prior checks of water/corrosion, red fuse box, salmon relay contacts as well as an electrical check of the motor regarding a short.
 
wetpee said:
Initial position of the roof when it failed:
file.jpg

This can't be the initial failure position, as your trunk lid is already opened in the service mode
 
everything in that picture is as it was when it failed except the trunk lid. by internal o-rings, do you mean the small o-rings around the plastic ends on the hoses that plug into the aluminum block on the pump assembly?
 
wetpee said:
...small o-rings around the plastic ends
There is really no plastic, it's metal.

wetpee said:
..the small o-rings around the plastic ends on the hoses that plug into the aluminum block on the pump assembly?

No, I meant the o-ring on the brass valve on top of the pump. Can't be replaced. I've already shot one pump to hell by doing this under hydraulic pressure.
 
thee89 said:
... until yesterday i had driven somewhere with my top down, and i began closing it but it got stuck halfway.
Is that the situation, that led to the position on the quoted photo?
 
Everything about that picture is how it was when it failed EXCEPT the trunk lid. we used the emergency pull cable inside the trunk to open the lid by reaching through the opening. you may not have emergency trunk pull cables in germany, but i believe they are required by law here in the US.
so replace the o-rings on the 2 hoses we disconnected? what about the internal o-ring for the brass screw? best to just focus on switches, sensors and wires to see if we can get it going again and see if it leaks?
 
Thanks for clarifying.

Well, as written already several times. Don't touch the pump except it's lying under water and has massive corrosion on the lower side of the motor.
 
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