E89 Error A690 (Roof) but everything seems fine (see photos and you tube)

[Ed-Raket]

Hello, I hope someone can help me, I have an error code A690 but I cannot solve it.
I measured the switch, it's closed ( part 01). Then measured the wire to the CTM
( part 02/03 ). Then the whole wire with the swich ( part 04 ), wires are 22 and 9.
Still I keep getting the error message so I must be overlooking something...
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BMW Z4 (E89) Error A690 - 01

https://www.youtube.com/watch?v=i89kHMGf3ZQ

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[javis20]

Did you measure the resistance of the switch both opened and closed. It's not a simple open and closed switch. There are resistors in there and a specific resistance value in both conditions. Pressed should be about 2.7k ohms. The un-pressed resistance is 550 ohms.

 

[Ed-Raket]

Thanks for your comment. No, I have not measured that. What I have to try now is to open the rooftop via a jump wire from pin 9 to pin 11, which should work I hope.

 

[flybobbie]

Why are you jumping 9 to 11?
Look like power wires.

Past posts have shown the switches opened up.
They have resistor inside to monitor continuity. Seems they were poorly made with resistors coming loose.
The output is change in resistance or current at the module.

Best bet just replace the switches, not random shorting of pins.

 

[Ed-Raket]

Thank you for your response. Yes, I think it would indeed be better to just replace the switch. I thought it was a normal open/close switch..lol I also found a video about this switch on You Tube

https://www.youtube.com/watch?v=5rnTMEVJPfs

 

[flybobbie]

It looks like the resistors are surface mount, so the solder paste never attach component properly to the circuit board.
I think a few took switch apart to find the resistor just dropped out.
Never had any problem with this switch on my 2009 car, so probably a batch problem.
Be interesting to know if there's a common year of cars effected.

 

[RobbiZ4]

Seems they were poorly made with resistors coming loose.

It looks like the resistors are surface mount, so the solder paste never attach component properly

Have replaced dozens, but never identified this as an issue. Corrosion inside on the contacts as well as hardening of the green gummis over the years is the core problem with them.

That's the reason, why they are on my roof maintenance list.
https://z4-forum.com/forum/viewtopic.php?t=130932

 

[Ed-Raket]

Thanks for your response, the problem I also had is that the trunk did not open. Fortunately, there are a lot of options on the car, including an extra push button to open the trunk (see pic.) Only, how do I open hood 2 by hand because the 2nd part of the trunk also has to go up.

 

[RobbiZ4]

E89: Retractable Hardtop (roof) Maintenance (and additional) tasks
https://z4-forum.com/forum/viewtopic.php?t=130932

4 simple maintenance tasks:
- check if there is any water on the bottom of the trunk or below(!) the hydraulic pump's foam
- renew 2 salmon relays
- renew 2 microswitches on the rear rams
- check both hallsensors on the right ram against traces of rust
Just do it!

Done this, there are in most cases only 2 possible issues:
- broken sensor wires in the rear roof shell
- broken wires in the locking system of the trunk lid

Identical posts worldwide:
https://z4-forum.com/forum/viewtopic.php?p=2055332#p2055332
https://e89.zpost.com/forums/showthread.php?p=30910617#post30910617
http://www.bmwz3club.fr/forum/viewtopic.php?p=1775733#p1775733
https://www.zroadster.com/forum/threads/dachstoerungen-klappdach.146153/post-3634310

 

[Ed-Raket]

To solve the error code A690, the hood must be in service mode (pic 1).
To be able to do that, the system has to work completely, but it doesn't because
there is an error.
There is a (temporary) solution for this and that is a "jump wire" so that the system
thinks everything is fine and you can put the hood in service mode and then start the
switch to be replaced. In this case you place the "jump wire" on the connections of the
CTM No: 9 to 11. No: 9 is the signal wire (Brown) that comes from the switch that sends the error code
indicates left and No:11 is the signal wire that has the same function but on the right.
By doing this, the hood thinks that everything is fine and you can put the hood in service mode
and replace the switch.
Below are some examples (photos and you tube) of a Jumpwire in another place in the Service mode.
==================================================== ====
BMW Z4 (E89) Service Mode

https://www.youtube.com/watch?v=6fjEvoJ--rU&t=10s
==================================================== ====
BMW Z4 (E89) Operation switch Part No.: 54377228585

https://www.youtube.com/watch?v=5rnTMEVJPfs&t=22s
==================================================== ====
BMW Z4 (E89) Operation switch Part No.: 54377228585

https://www.youtube.com/watch?v=eKjn9OVaiKI
==================================================== ====
BMW Z4 (E89) Repair Switch

https://www.youtube.com/watch?v=qcwZC1uah_o
==================================================== ====

Thanks to everyone who contributed.

 

[javis20]

Great job Ed. I'm surprised that you can jumper both of those microswitches together. I carry a spare microswitch and hall sensor in my boot, just in case. Did you by chance measure the resistance of the bad microswitch?