Wipers, L/R indicators don't work
 

Hey guys big thanks to y'all already. I have a e320 2001 ... My brother washed the engine with power wash. After that, whatever that controls my wipers, signals next to the steering wheel don't work. However, if I press the emergency light, it works! Plus if I turn on the lights and push that controller to turn high lights, it works too.
Im confuse, I don't wanna take it the dealers for sthg fixable by me. Please help thanks