R129 Horn Quit

[Mike Miller]

My horn has been acting up. It was intermittent, requiring steering wheel movement to get any action so I figured it was not the horn relay, located in back of the fuse box, left rear hood. I removed the air bag to check for wires or bad slip ring. What I found was a horn relay in the cavity!! This threw me off. I checked the integrity of the wiring to the relay and cleaned everything, without removing steering wheel or messing with the slip ring. The horn appeared to be working again. I put it all back together, the horn worked three times and quit completely

I will take any suggestions. I would also like to know if that relay in the steering wheel is supposed to be there. It seemed funny as it did not have a MB part number or star on it (made in Portugal) and ALLDATADYI does not show it.