[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.