So I believe I caused this but not sure for which reason...I'm just a google/YouTube mechanic.....my brakes were bad so went to get new rotors pads etc.. but I ran .through a car wash on way home ,and my fuse panel covers were not over fuses under hood.. don't think it had any effect

Anyways battery went dead while on jack so I jumped off auxiliary battery to get in trunk...but I hooked the pos cable up to the big -2 gauge red positive and the negative to the other small terminal.which is apparently hot as well not knowing just to use the metal brace on back of car..

But now all my lights are flashing non stop while driving,..,, fog lights, tail lights ,all interior etc...... where do i start

If anyone has a good solution on what to do Will pay 50$ reward in BTC. I've checked the fuses , checked main battery,check all ground connections. Mechanics just tell me they not sure what they can do .besides test everything in entire car. I also have a bad exhaust rattle all of sudden ,is there maybe a ground connected underneith.

you better go to a mechanic that has star diagnostics. that computer should pinpoint the problem. you may have blown one or more modules like the sam.

what year/model of the vehicle? I assuming its the s550 w220 from your avatar? If you put the negative cable on that smaller power side cable then you caused a short to power in the system. if your lucky you are only dealing with blown fuses but you can very likely damage many control modules. If its the w220, why didnt you just manually open the trunk and jump right at the battery?