[jamesworts]

Hi All, 

I have a customer with a 2000 clk320 convertible and he is having problems with the horn and also the roof. 

I have tested the horn by going into SAM and activating the horn and it works fine, but pressing horn on steering wheel does nothing.
I have replaced the squib but this makes no difference. 
The buttons on the steering wheel also appear to do nothing as well. It does have aftermarket stereo in it, so don't expect it to work the stereo, but should still operate the instrument panel? 

The illumination on the steering wheel buttons do work, so must be getting power and signal. 

Any idea about this? 

Next is the roof, open the roof and all 4 windows go down, but then nothing else. Only fault I am getting is limit switch supply faulty. 

Appreciate any help with this.

[gcs190]

Regarding the horn: if the problem is not in the actuating part, it must be in the sensing part, diagnose it in the column module, which from what you say seems to be the problem.

For the issue of the roof, perhaps you should study how it works and the maneuver strategies, it is IMPOSSIBLE to give you an orientation with the data you provide, determining the problem is easy if it is known the system and work on it.

[jamesworts]

Regarding the horn: if the problem is not in the actuating part, it must be in the sensing part, diagnose it in the column module, which from what you say seems to be the problem.

For the issue of the roof, perhaps you should study how it works and the maneuver strategies, it is IMPOSSIBLE to give you an orientation with the data you provide, determining the problem is easy if it is known the system and work on it.

Hey,
Thanks for this, 
I forgot to mention that I replaced the squib and module in one.
I now have a front SAM to try on it tomorrow.

Thanks
James

[gcs190]

Regarding the horn: if the problem is not in the actuating part, it must be in the sensing part, diagnose it in the column module, which from what you say seems to be the problem.

For the issue of the roof, perhaps you should study how it works and the maneuver strategies, it is IMPOSSIBLE to give you an orientation with the data you provide, determining the problem is easy if it is known the system and work on it.

Hey,
Thanks for this, 
I forgot to mention that I replaced the squib and module in one.
I now have a front SAM to try on it tomorrow.

Thanks
James

Replacing parts is going to give you more problems than you already had and it's also absurd when you can check if they are defective or not. I will never understand that bad habit of changing parts without having  performed a diagnosis and reached the conclusion that the problem is there: slow, expensive and no guarantee repairs that only depend on luck

[jamesworts]

Ok, so an update. 

Unbelievably, it was all down to a fuse!!!! 

Under the bonnet there is a fuse for "Airbag Warning Light" THIS also supplies the steering wheel controls and horn! 

It was missing from the fuse box. What a nightmare! 

Solved!