Just bought a 2013 ML 350 and it’s saying blind spot assist inoperative on display. Doing some research online was to clean and inspect them. Found the two In back bumper easy enough and we’re buried in dirt but other than alittle stain rust on them I don’t see anything obviously bad with them. Cleaned and dielectric greased them and reinstalled. On the front of the car there is one on the passenger side but nothing on the sensor compartment on drivers side, is there only one on the front normally or is it missing? I don’t see any wiring to the location either but thought it was strange to have the compartment and nothing in it. Maybe a past accident and the wiring never got out back? Or just only one to begin with on the front???
thanks in advance for the help..
also the system does work apparently for the inbumper sensors because when pulling in and out of the garage it notifies of close proximity objects.
also the lane departure is working

Actually just working on this on my FIL vehicle which is a 2012 ML 350 W166.

There are 2 radar sensors in the front, both are the same part # A 000 905 00 10. They are also prone to get water infiltration and eventually deteriorates the unit which is what happened in our case. The front right - Passenger (B29/3) was in good condition but the front left - driver (B29/2) had clear signs of water damage and the white cover of the radar sensor was split open, no way of cleaning or salvaging it.

See diagram for the location of the sensors. I had access to Xentry so was able to pin point which one was faulty and to test the wiring, I switched the 2 front sensors which resulted in the fault moving to the other side. Looking to now purchase a new sensor.

Thanks for the info, could it be possible that the 2012 has a different system? It blows my mind that the drivers side sensor for the front was not there if it’s supposed to be there… it’s just an empty mount inside and no wiring in sight. I don’t know the history of the car as we bought from an individual and they just said the system didn’t work and didn’t bother to fix it.

It is possible but also should have mentioned that the 2012 I’m working on has the Distronic system. My GL350 is 2013 and does not have Distronic and only has 1 sensor.

Sorry but I just assumed yours had Distronic, you can check your VIN to get a data card on your vehicle at the following link https://www.lastvin.com. You mentioned you just got the vehicle so the data card will help you understand the options your vehicle has.

Is it possible to tell from MB code U11A687 which blind spot sensor is bad? I’ve got the Autel mk808 and it says there is an error with that code but won’t communicate with the system to diagnose each sensor for some reason.
thank you in advance

Unfortunately, I am unable to determine which sensor is bad with that code. Maybe try opening the access cover for the front sensor to see the physical condition of it, that may be a start as there are quick tell tale signs of damage (splitting, corrosion, etc). This was the case with my FIL's ML, was really bad and appears the previous owner at some point messed around with it.

Find a local Indy shop that works on euro vehicles and see if they may be able to diagnose or as a last option, take it to the dealer (I know the cost is not ideal) and let them diagnose it and tell you which sensor is bad.

If you were local to the Greater Toronto Area in Ontario, I would've helped out and hooked it up to Xentry.

So just an update on my FIL's radar sensors, he has had this issue for a while but just ignored it as it was not affecting the vehicle's operation.

I ordered the replacement sensor that I found damaged and not working based on what I saw in Xentry, Part# A000 905 00 10. Bought a used one on eBay out of UAE for about $375 CAD shipped. Just arrived and will be installing it this weekend. Will try to take snapshots of the replacement and if I have to do anything in Xentry to relearn or adapt, I'm learning as I go, so will share what I find.

Here are some pictures of the old and new part, guess which one is the old one...

Thanks for the update. Seems to be a weak point along with the wiring harness depending on climate conditions. Dealer price is $972 each, so you did good!

UPDATE - Replaced the driver front radar sensor this weekend and no adaptation or relearn was needed. Errors messages on the dash which appears each time the vehicle is started cleared which were "PRE-SAFE Functions Limited See Operator's Manual" and "Active Blind Spot Assist Inoperative".

Took vehicle for a test drive and blind spot sensors are working and detect when a vehicle is in the blind spot zone. All fixed.

I have the same problem. Wrong left rear and front radar. But , I have bought one sensor and changed on the front. PreSafe function and Distronic still inoperative. I understand that ActiveBlindSpot is not working because left rear sensor is faulty. But I checked errors with diagnostic and only rear sensor have error codes. No errors from front sensors. I am confused , are the rear sensors necessary for PreSafeFunction and Distronic ? Can you help me ?

Not sure if the functions are dependant on each other but would have to assume so.

You mentioned you changed the front sensor and no longer get errors from the front. Perhaps you should change the left rear sensor, clear codes and test again for any issues.

I didn't have to change the rear sensor but if the sensor is the same part#, maybe swap it with a front sensor to see if the error follows to the front to 100% confirm the rear sensor is faulty and the issue, which when replaced, should resolve your issues.

A news. I tried a sensor from my friends car (also ML W166) and everything worked fine like in yours case. If my new sensor don't have any errors but not work I assume that really needs to be adopt. Some guys with Xentry diagnostic told the same.
So now I have to find somebody with these possibilities because orginal Mercedes garage has a crazy hourly rates. :-)

You can get your own xentry for really cheap
Need one older laptop has to have I5 or I7 processor
and passthru interface I have Chinese copy Tatrix 2.0 it was $20 on Aliexpress
there are sellers ebay who will install xentry for you fairly cheap like $20-30
it will work offline mode only but many things can be done almost everything calibrated or adapted
and for sure you can calibrate your sensors

I will check these options. :-) Thanks.

Can you help me ? I have found a Xentry on Aliexpress. This is software only. But I need a diagnostik equipment too because I have one but it's not compatible with Xentry (as supplier just told me). So can you suggest me somethnig ?

Can you help me ? I have found a Xentry on Aliexpress. This is software only. But I need a diagnostik equipment too because I have one but it's not compatible with Xentry (as supplier just told me). So can you suggest me somethnig ?

I bought this one one year ago
and works just fine with mercedes

https://a.aliexpress.com/_mqJFZm2

and there is this Russian forum :
www.smartland.am

They have really good information about
mercedes software and other cars
it is in Russian but works fine with google translate

I paid like $2 for one month access to download files
If you not comfortable with installing xentry , just get one of those remote installation
from ebay or aliexpress

So OpenPort. I saw that but not sure if it is enough. Thank you .

https://www.aliexpress.com/item/1005...63661802pz2TyO

That's what I use. Its not cheap but it works with Xentry.

Can't see that . (Sorry, this item's currently unavailable in your location.) is the message.
Are you from Slovakia ?

I bought it from Canada. Search the item number.

So I finally have a Xentry ready. It's working. And now, can anybody help me please how to adopt/coding a front left radar sensor ? I have one installed (from US) but I need to code this with Xentry. I don't know how. But I have only offline coding options. I don't have an online login.

Dunno what year you are working with but on my 2013 no coding is when changing radars.

Do you know where the wiring harnas have a weak spot?
On mine 2013 fuse 116 blows so there is a shortage somewhere.... And maybe you or someone knows where cables go, so i could check them...

The entire wiring harness on these cars is a complete joke. There's connectors exposed everywhere with minimal protection and crappy connections of wires into connectors. In the specific case of the radar sensors the design is fundamentally flawed in that they are located with no protection in one of the most extreme environments on the whole car. I suppose directly over the wheels would be worse but not by a whole lot

There's a variety of suggestions online about how to improve the chance of your system surviving. Protecting the seam around the radars is a common theme. Personally I'm not too concerned about that but there's no particular reason why you should follow my thinking so that may be a concern to you. I think in my own case the connections to the radars, the connectors themselves and in particular the way the wires enter the connectors is the root of my trouble. The unprotected wire entry allows salt water to enter the back of the connector, wick along the wire/terminal and eventually rust the mating surfaces inside the connector. Then it may further proceed into the radar unit itself.

I'm waiting for a couple of connector pigtails to arrive at which point I will cut the existing (crap) connections off and solder on the new ones. Before I reassemble the system I will paint the entire wire assembly & connection with liquid electrical tape. I've also seen recommendations to use self amalgamating (silicone) electrical tape. That stuff can be a PITA to use and I see no advantage over the liquid tape but YMMV. I suspect that will cure my current intermittent problems but right now I simply don't know for sure. I am however convinced that the three year ordeal I have endured is entirely due to MB wiring which resembles the crap you see in slapped together stick and staple RVs.

As for routing on that rear harness: On my 2013 it comes off two connectors in the rear driver side quarter panel area, directly behind the rear wheel - yet another poorly located spot. There are two plugs there. The harness proceeds past the DS radar and then into the bumper surround where it connects to the 4 rear parking sensors. Eventually it terminates at the passenger side radar. Changing it requires removal of the bumper surround.