gpouliniii

I recently replaced my factory 18"g on my 2016 C450 to some 20" AMG wheels and my park assisthas been freaking out when I firsgt turn my car on and then turning its self off. AQnyone ever had this problem?

chassis

More detail please. What is actually happening? Use lots of words to describe. Or a video.

gpouliniii

Thanks!

So, I had the the new wheels put on and everything seemed to be working just fine and then we got that big snow storm and the sensors went beserk and going off constantly, so I took it to car wash and had it cleaned etc etc. So now when I start it up the 4 red lights in the instrument cluster and the ones above the rear by the third break light go off for about 10
seconds and then goes off, but it turns the park assist off after all of that. So if I turn it back on, it just does all of that all over again and turns itself off. It’s kind of annoying

chassis

What other modifications are on the car?

gpouliniii

Nothing on the body or anything like that. Dual air intake and a racechip, but thats about it.

chassis

Can you remove the chip and see if the same thing happens?

gpouliniii

Yes, I will try that out. I've had the chip on there for months and it just started doing it when we had that bad snow storm. Ive washed the car a few times since then. Ill try removing the chip tonight and seeing if that fixes it. Thank you for your help with this.

gpouliniii

I took the racechip off and its still doing it. When I start it up, all of the red lights in the dash and above the back window light up and then go off and it automatically turns the park assist and active motion detectors off. When I hit the button to turn it back on, it just does the same thing and turns itself back off. When we had that bad snow storm and everything turned to ice, I remember a warning message in the dash saying I had "obstruction on the parking sensors" or something like that pop up, but I also had low air pressure in my right rear tire at the time and I was just hitting the "back button" for a couple days until I had it fixed. But I havent had it fixed yet because its warmed up and the tire is no longer losing air. I had new wheels, tires and sensors put on, so I figured it was adjusting to the weather and/or sometimes certain wheels let air out when it drops down below freezing. Any ideas? Or should I just take it in to the shop? I'd hate to have to pay a crazy amount of money for something I could have fixed myself. Thanks again for your help!!

chassis

There has to be something else.

A weak battery can cause otherwise unexplainable problems. You can replace the battery and see if it fixes the problem, or you can dig further into seeking an electronic problem with the tire pressure system, parking sensor or the chip/mods. You need to get the car to a known good state.

gpouliniii

Just installed a brand new main battery and a brand new auxiliary battery 2 months ago. Do you think by me adding 20" tires that are wider would do it?

chassis

I wouldn't rule it out. The vehicle has a chip and the wheels and tires are modded / not factory. Try changing back to factory wheels and tires if you still have them. Please post a front-on photo of the vehicle showing how the front wheel/tire relates to the body sheet metal.

Paxfobiscum

Bring it to a dealer, plug in the diagnostic too, get the codes and see what they say.