I have a 1999 C230 my sister gave me. It runs and drive great but came with some problems. The wipers, turn signal, windows, and horn don't work. My understanding was they stopped at the same time. I have read about a "comfort module"' but don't know much about it. Any advice???

 

Maybe a weak battery?

 

Don't think so. I have driven it about 7000 miles. It's starts fine and runs fine.

 

So does My c280 but before i fully charged the battery my car had similar simptoms

 

You don't have an issue with the battery voltage----your issues are with the relays are faulty---look in the front SAM!!(horn-wiper bla bla)