CLK320/A208 Rollover Bar/Soft top ECU - B1091

[karlos111]

Hello,
I bought my CLK320 A208 with ongoing problem with the windows and soft top not operating properly. Originally this was occasional and for short while, but now is every day. In the morning the car is fine and windows work as it should, but after a while the red light for the soft top comes on and windows die. The soft top never really worked for me, but previous owner said that is fine now and again.
Few days ago I manage to plug it to a star diagnostic equipment that came with B1091 fault code- fault in communication with control unit N52 roll over and soft top module. The roll over bar is working fine while the switch light is off and I do not think is down to a micro switch.
Previous owner has been disconnecting battery to reset ECU's for some time and has been jumpstarting the car. Could that be the reason?
Also if ECU is faulty, can it be replaced with another second hand unit without programming to the vehicle?
Will appreciate all opinions and thoughts on the matter
Thank you

 

[jamesmc]

.........CLK320 A208 with ongoing problem with the windows and soft top not operating properly.

I assume by that you mean the windows are not operating properly when you try to operate the roof mechanism?
i.e. Windows operate normally but not when trying to operate roof.

If so.... try replacing/swapping the relay fitted to the hydraulic roof pump. The previous owner of my car had a similar problem and advised that they replaced the battery which apparantly it fixed the problem, but after the roof and windows just stopped playing ball. Red light flashing on the switch and nothing else.

A quick (cheap) check is by swapping over the fuel pump relay with the roof pump relay, both fitted in the boot and both the same part number.
The roof pump relay is fitted to the pump itself and is not so easy to get at, but the swap can be done through a hole already cut into the panel fitted to the rear of the pump, without having to remove the panel itself. I needed my other half's smaller hands to achieve this.

 

[karlos111]

Thanks for the reply,
my windows only work in the morning prior to switching the engine off at the end of the commute to work and in the afternoon the soft top switch light comes on and they die/stop operating/. Along with that the rollover bar switch light comes on as well.
If i turn the knob for the soft top in the morning the windows will go down automatically, but the soft top would not wind itself.
Pretty sure is the ECU unit, but will take all ideas on board.
Than you again

 

[television]

This is almost like a can communication fault or maybe just a door module.

It would seem that the windows have no stored memory, the same with the roll bar. the roof cannot go down if it does not know where the windows and roll bar are.

First re set everything.
Hold the roll bar up for 10 sec with the key turned to 2
then close the windows in turn and hold the switch up for 10 sec in key 2

 

[Cole@MBS]

Sounds like the softop control module has gone down! thats not cheap!!

 

[karlos111]

Are they codded to the vehicle? can I replace it with second hand one without programming?

 

[Cole@MBS]

You might be lucky but im unsure to be truthful, never fitted a 2nd hand one before!!

 

[jibcl500]

Check the running voltage of the battery, if the voltage is below 13.4 volts then there could be an issue with voltage to the ECU's and hence the problem.

jib

 

[karlos111]

Hello,
I did check the voltage -13.85 to 14.00. Did try to reset the head rests as Television sugested above but did not work either. Any other ideas anyone? The window/roll over bar fault comes every day as explained before.

 

[television]

It must be worth plugging the car into STAR to get an indication of what is going wrong

 

[karlos111]

already did - B10911

 

[karlos111]

my mistake -B1091

 

[karlos111]

Hello again fellas,
Just changed the ECU with another one(second hand one)and soft top warning light is now gone, but the one for the roll over bar came on! Soft top is still dead thou.The rolloverbar is working just fine, but the light stays on for some reson,which I guess stops the soft top of working. I did try reseting the rollover by holding the switch on for 10sec-did not work.
Any ideas anyone?

 

[Cole@MBS]

Another plug into star with the newer ecu on the car!!