Hello Everybody!

I own 2008 W221 S500 with Distronic Plus, Blind Assist, Parktronic and Parking Assist options. Both of my original bumpers had 4 big radars and now I have replaced them with 2013 versions. However according to my 600+ images research restyling 2013 bumpers only have 2 radars in each bumper but also regular small round parktronic sensors. There are 2 inner in front bumper for Distronic plus and 2 outer in rear bumper for Blind Assist. Currently my "extra" radars are held in their original place (like it was in old bumper) just buy handmade clamp however I want to make these system work as designed in 2013 models. I guess Blind assist don't need extra 2 radars in front and it somehow uses some other device to detect other cars in front and 2 extra radars in rear bumper are replaced by regular round sensors.

What hardware and software adjustments are required in my case?

It's likely the bumper you purchased isn't correct for your car which should be a bumper with no partronic circular cutouts. Your car is coded for 4 radar units back and front and if you alter that you will have problems with Distronic, Blind Spot, etc.

Yes the case is like you described but is it possible to code this car to use 4 partronic sensors with 2 radars per side instead of 4 radars?

You would need a harness that supports that hybrid configuration.

I think the wiring harness would be the easy part, compared to getting the firmware cobbled together to make it work. I’m going to go out on a limb and guess that the two different types of sensors would require very different software.

The easy part would be to have gotten the correct bumper in the first place.

Very true! Failing that, a decent shop could probably fill those holes and repaint…. Or just find a not-too-ugly way to fill them.

are u sure the small round visible ultra sonic parking sensors can take the place of the two smaller radars at the front?

on the early cars the smaller radars are to help at low speed to pick up on what's going on around it in town