e89 roof problem

Zed Baron said:
Hope you get it sorted soon Sean :thumbsup:

Me to dude - should have some info this morning, he will do an hour diagnostic and then stop and call me as after that he needs my approval to continue but I have told him its 95% certain its microswitches.
 
RobbiZ4 said:
I'd say, same story as the following on the other Z4 channel: :wink:
https://e89.zpost.com/forums/showthread.php?t=1843991

Microswitch coupling lock on both sides of the hydraulic rams in the boot. Not the microswitches in the roof shell!
 
RobbiZ4 said:
RobbiZ4 said:
I'd say, same story as the following on the other Z4 channel: :wink:
https://e89.zpost.com/forums/showthread.php?t=1843991

Microswitch coupling lock on both sides of the hydraulic rams in the boot. Not the microswitches in the roof shell!

I believe so, only spoken with the receptionist at th moment but will have more info tomorrow
 
Car back and sorted, microswitches was the issue and it was the ones Robbie said.

Covered under warranty apart from £50 which I am happy to pay as any issues and back to the garage. :thumbsup:
 
Ole gits rule said:
Car back and sorted, microswitches was the issue and it was the ones Robbie said.

Covered under warranty apart from £50 which I am happy to pay as any issues and back to the garage. :thumbsup:

Result, even with a small excess :thumbsup:
 
Yep, was £35 for the switches so for £15 I am happy to let some else mess with it.

Especially when I collected it and the roof would not budge, took them 45mins of messing to get it to go, they had to move the switch.
 
Ole gits rule said:
Yep, was £35 for the switches so for £15 I am happy to let some else mess with it.

Especially when I collected it and the roof would not budge, took them 45mins of messing to get it to go, they had to move the switch.

Congrats!
The problem is, that in most cases the faulty switch can't be measured with an ohm meter. The MS are not broken, but their timing doesn't fit anymore to the allowed tolerances.
One day it works fine, the other day the roof stops anywhere.

Excellent to recognize with my
Y3 Roof Diagnostic System
https://z4-forum.com/forum/viewtopic.php?f=23&t=129048
 
RobbiZ4 said:
One day it works fine, the other day the roof stops anywhere.
I am not trying to be difficult, honestly, but I don't understand why that would be Robbie? As I understand it the bootlid ram microswitches are not functional until the last part of the bootlid (trunklid) cams pull the panel down and so momentarily make the switches. Why would this have a bearing on the whole process stopping randomly?
Also, why would an ohm-meter be useful to determine the operation of a switch? A continuity tester, I can see.
I am genuinely interested to gain more knowledge into how the process works, as I have a reasonable knowledge of electro-mechanics but know nothing about electronics.
 
RobbiZ4 said:
Ole gits rule said:
Yep, was £35 for the switches so for £15 I am happy to let some else mess with it.

Especially when I collected it and the roof would not budge, took them 45mins of messing to get it to go, they had to move the switch.

Congrats!
The problem is, that in most cases the faulty switch can't be measured with an ohm meter. The MS are not broken, but their timing doesn't fit anymore to the allowed tolerances.
One day it works fine, the other day the roof stops anywhere.

Excellent to recognize with my
Y3 Roof Diagnostic System
https://z4-forum.com/forum/viewtopic.php?f=23&t=129048

That is what happened to me, worked force when I went out but played up when I came back - sodding pain as I do not have a garage but my neighbour does so I parked in there overnight as the windows were down
 
Pondrew said:
...so momentarily make the switches. Why would this have a bearing on the whole process stopping randomly?
Also, why would an ohm-meter be useful to determine the operation of a switch? A continuity tester, I can see.

Well, these microswitches are not only simple switches. They also carry 2 resistors internally, one in a row, the 2nd in parallel.
It's not a simple switch, there is always a current flow between the 2 wires of a microswitch. That's why you can diagnose it with an ohm meter: 570 ohms vs 2.770 ohms are the standard values.

The Cabrio Top Module (CTM) always checks the presence of all sensors as well as of all actors. If a wire is broken the CTM can identify it. If there is a short between 2 sensor wires , it can be detected as well. In addition, the 2 states OPEN as well as CLOSED.

The problem over the years arises by corrosion inside of the switches. Depending on the weather, the humidity inside of these microswitches can differ: the one day it works fine, the other not.
 
RobbiZ4 said:
Well, these microswitches are not only simple switches. They also carry 2 resistors internally, one in a row, the 2nd in parallel.
It's not a simple switch, there is always a current flow between the 2 wires of a microswitch. That's why you can diagnose it with an ohm meter: 570 ohms vs 2.770 ohms are the standard values.

The Cabrio Top Module (CTM) always checks the presence of all sensors as well as of all actors. If a wire is broken the CTM can identify it. If there is a short between 2 sensor wires , it can be detected as well. In addition, the 2 states OPEN as well as CLOSED.

I didn't understand most of that Robbie, but I know you have more knowledge than me.
However, I have taken one of these switches apart (just for fun and out of genuine interest) and cannot find any resistors in there.
 
Pondrew said:
... and cannot find any resistors in there.
LOL.
Where did you search for it?
You have to cut out the housing, then you will find a green circuit board. There are 2 SMD resistors soldered on it. One with 570 ohms, the other with 2.2kohms. In total 2.770 ohms, depending on the switch state (opened or closed).
 
Are they are SMT (surface mount resistors), tiny squares on the board maybe?
 

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