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There is coverage for Blind Spot Sensors, ask your service advisor. If you're replacing the harness already, it doesn't matter if they get wet or not. Mine have been disconnected for two weeks and I've driven in rain and snow without more lights coming on, on the dash, you can't short the system anymore from what I've heard. You can stick your hand underneath the bumper (it's gonna be tight) to disconnect them.
Currently waiting on parts as there is a global back order from the chip shortage. Soley disconnected mine since the issue has caused a widespread CAN Error in the car making it undrivable.
I just wanted to update this thread with my recent experience in case it can help others in the future. I started getting "blind spot assist inoperative" message in the dash during a recent 400 mile road trip. The message started on day 1, coming and going as I drove. On day 2 it triggered more warning messages, and basically all safety systems and traction control became inoperative, but the car still drove normally. After sitting a few hours and restarting all but the initial message went away and the car drove normally.
Upon getting home I scanned the car with my Icarsoft MBII and noted that I could communicate with the left rear radar module but not the right. The space where the modules sit is tight but I was able to remove both without removing the bumper. From there I swapped places with the modules and the problem moved, so that confirmed it was a bad module not wiring or something else. I had seen some other videos where people tried to clean them but I didn't have any luck with that. I was able to find a used part on ebay with nearly all matching numbers (the "Q#" didn't match up) and it was plug and play, no coding necessary. I sealed the cases with exterior caulking and put a decent layer of dielectric grease around the plugs to hopefully help seal out water. Others may wish to do this as a preventative measure rather than wait for an issue. This simple thing *may* strand you somewhere.
Message received trying to communicate with right rear. I pried the case apart by gently prying around the seam with a utility razor Looks like this chip is blown out Sealed with caulking
I just wanted to update this thread with my recent experience in case it can help others in the future.
I started getting "blind spot assist inoperative" message in the dash during a recent 400 mile road trip. The message started on day 1, coming and going as I drove. On day 2 it triggered more warning messages, and basically all safety systems and traction control became inoperative, but the car still drove normally. After sitting a few hours and restarting all but the initial message went away and the car drove normally.
Upon getting home I scanned the car with my Icarsoft MBII and noted that I could communicate with the left rear radar module but not the right. The space where the modules sit is tight but I was able to remove both without removing the bumper. From there I swapped places with the modules and the problem moved, so that confirmed it was a bad module not wiring or something else. I had seen some other videos where people tried to clean them but I didn't have any luck with that. I was able to find a used part on ebay with nearly all matching numbers (the "Q#" didn't match up) and it was plug and play, no coding necessary. I sealed the cases with exterior caulking and put a decent layer of dielectric grease around the plugs to hopefully help seal out water. Others may wish to do this as a preventative measure rather than wait for an issue. This simple thing *may* strand you somewhere. .../... Sealed with caulking
Nice DIY fixing
The one thing I suggest you should finish is the silicone job.
The case top and bottom are perfectly thermo sealed together. A doubled up seal all around can't hurt anything.
The original water penetration is by capillarity through the wiring harness connector seals.
Last edited by CaliBenzDriver; Mar 20, 2023 at 10:11 PM.
Don't take any body's words for granted... instead trust evidences of reality!
Thanks @up_too_late for providing us with investigation pictures. You get taylored inputs!
So here is what we have: connector area is 100% saturated
Connector pins are fully/partially oxidized
unsoldered connector 😳
In conclusion, you should reseal all your exposed "waterproof" connectors.
> Plan B:
If water doesn't get your radars now, solderless and vibrations eventually will.
It is possible to simply disconnect a radar module if it's actively messing up the whole CAN-B string.
Last edited by CaliBenzDriver; Mar 21, 2023 at 02:28 AM.
2014 E350 Sport (sold), 2015 S550 Sport (sold), 2018 S560 Sport (sold), 2018 GLE43, 2014 E550
Well I'm in this camp now too.... question, there seems to be a million part numbers for these things, will any one work? Or do I need one specific for my VIN? Also, anyone try the knock offs or is used better?
My 2016 E350 displayed the the "Blind Spot Inoperative" message a month ago. I removed and found one upon opening the case to have what looked like a burnt component on the board. I found two used monitors from a 2016 E450 with nearly all identical identification numbers. After installing, I still get the error message. Not plug & play. Understand I may have to commission them to the ECM. I'm been interested in purchasing a scanner and wonder if one can commission these by way of a scanner which communicates. Has anyone experienced this? If so, any recommendations as to what scanners to consider?
Try swapping sides with your original units and see if the problem follows the suspected unit. If the problem moves then its the unit, if it doesn't it's likely your wiring harness. If it helps, I matched the circled numbers with a used unit on ebay and it was plug and play.
2014 E350 Sport (sold), 2015 S550 Sport (sold), 2018 S560 Sport (sold), 2018 GLE43, 2014 E550
I bit the bullet and got new harnesses and sensors at the below site. They seemed sketchy but they are legit. It was more than I wanted to spend but they're new and OEM. Also best price I could find (under 900 for everything).
Fyi my left rear sensor died, so I thought. No valid codes or clues other than Xentry said it couldn't communicate with that module. I don't even use that sensor but it still caused all kinds of grief with the car, sheeze.
While I was trying to get the sensor out for a look-c, without luck, I decided to trace the wire and maybe unplug it elsewhere, or just cut the F'er, and that's when I found the actual problem. F'in Rats chewed the harness! The harness on mine sits just above and aft from the bumper, the actual steel bumper, so it looks like the Rat was on the bumper and, oh look, a wire right here at head height for me to destroy for no reason. So the ******* chewed about 24" of it, which was about the length that was conveniently positioned for the little F'er. I guess, judging from what must have taken a log time based on the damage, the wire must be tasty to Rats? So add that to the list of things that can cause this sensor to fail...
This thread is incredibly encouraging. Been having car start issues for several weeks. Push button stopped working but using key in ignition eventually works. Had Autozone run a check and it produced the list of DTC codes below. Then took it to MB dealership to run diagnostic and they said bad battery plus it’s likely a faulty rear radar sensor causing a short in the CAN string / electrical circuit. MB quoted $2300 to remove bumper to replace rear radar sensor and possibly wiring harness which they think, but are not sure, may be causing the short which is causing problems getting the car to start and draining the 10 month old battery… chicken or the egg. No way can I remove the bumper myself but after reading this thread I do think that I can simply squeeze my hand in there and disconnect the radar module and then will order parts and possibly replace the sensor…… with bumper in place….. and replace the battery still under warranty.
AutoZone ran diagnostics and got these DTC codes:P0562 system low voltage, power supply too low;
U042900 implausible data received from steering column:
U0426 Start Enable Signal not issued by Drive Authorization System:
U015531 Comm w Instrument cluster has a malfunction. Signal is not present.
ABS C028300 &C02A400 undervoltage detected;
C078200 CAN msg from Contriol Unit ‘N68 (Electric Power Steering Unit’ is faulty;
C067A00 & C067C00 there is an internal fault in Control Unit Thanks guys!!!
This thread is incredibly encouraging. Been having car start issues for several weeks. Push button stopped working but using key in ignition eventually works. Had Autozone run a check and it produced the list of DTC codes below. Then took it to MB dealership to run diagnostic and they said bad battery plus it’s likely a faulty rear radar sensor causing a short in the CAN string / electrical circuit. MB quoted $2300 to remove bumper to replace rear radar sensor and possibly wiring harness which they think, but are not sure, may be causing the short which is causing problems getting the car to start and draining the 10 month old battery… chicken or the egg. No way can I remove the bumper myself but after reading this thread I do think that I can simply squeeze my hand in there and disconnect the radar module and then will order parts and possibly replace the sensor…… with bumper in place….. and replace the battery still under warranty.
AutoZone ran diagnostics and got these DTC codes:P0562 system low voltage, power supply too low;
U042900 implausible data received from steering column:
U0426 Start Enable Signal not issued by Drive
Authorization System:
U015531 Comm w Instrument cluster has a malfunction. Signal is not present.
ABS C028300 &C02A400 undervoltage detected;
C078200 CAN msg from Contriol Unit ‘N68 (Electric Power Steering Unit’ is faulty;
C067A00 & C067C00 there is an internal fault in Control Unit Thanks guys!!!
Now you know rear modules can be easily popped in 5mn. No need to pay book-charges to remove your bumper two times, once per side-radar - Actually no need to even drop bumper at all
Your list of faults shows how they are nested by nature. One helps creates the next.
Thus the KEY TO SUCCEED IS ALWAYS TO FIND ROOT CAUSE.
Rain soaked radars can be unplugged for chaos relief.
Take 5mn to spread RTV to seal your harness-connectors.
Buy your own scanner
Last edited by CaliBenzDriver; Nov 11, 2023 at 05:45 PM.
Can anyone pls clarify for me exactly which radar sensor system part can be popped out without removing the rear bumper… before I presume? Is it the square radar modules that can be removed? or is it the little round radar sensors? Or both? I understand it’s a tight squeeze so I want to be clear what my target is before I proceed.
Also, just checked the links t.kelley provided for parts purchase (albeit for different model than my W166 2015 ML350) and the modules are $300-500 and the sensors are $80-100. So I dont want to buy a part I cannot even access.
Thanks in advance
Last edited by RatherBeSailing; Nov 14, 2023 at 09:41 AM.
Reason: To add title
Can anyone pls clarify for me exactly which radar sensor system part can be popped out without removing the rear bumper… before I presume? Is it the square radar modules that can be removed? or is it the little round radar sensors? Or both? I understand it’s a tight squeeze so I want to be clear what my target is before I proceed.
Also, just checked the links t.kelley provided for parts purchase (albeit for different model than my W166 2015 ML350) and the modules are $300-500 and the sensors are $80-100. So I dont want to buy a part I cannot even access.
Thanks in advance
This one: corner medium range radar module (not my pic)
One of my sensor's went out, had one replaced before but it was covered. I was wondering if anyone has bought used from Ebay? They're about 70-80% cheaper, but they all say pre-owned or re-manufactured. Due to that, I was wondering if they would even last over two years? Can someone weigh in?
One of my sensor's went out, had one replaced before but it was covered. I was wondering if anyone has bought used from Ebay? They're about 70-80% cheaper, but they all say pre-owned or re-manufactured. Due to that, I was wondering if they would even last over two years? Can someone weigh in?
working sensors will last as long as water stays out of the connector and loose pins stay in contact with circuit.
My first ebay replacement documented in this thread did not last as I hadn't listened to CaliBenzDriver. I put a second one in, and this time took his advice to seal up the plug side of of the connection. So far, so good.
My first ebay replacement documented in this thread did not last as I hadn't listened to CaliBenzDriver.
I put a second one in, and this time took his advice to seal up the plug side of of the connection.
So far, so good.
the rear radar modules are directly sprayed by the rear wheels without any splash protection
Other candidates for proper harness waterproofing are located upfront (bumper /radars/temp; engine; steering) and under carriage with the tranny Intelligent Shifter Module connector (ISM: "Proceed to workshop without shifting...") located the lowest near muffler and the main single GND Strap.
Several months ago I put a cheap new pair of blind spot sensors from Wal-Mart.com in my ML350. No issues and they were exact matches for OEM. Frankly, I'd be surprised if there's more than 1 maker of these and everyone just puts their badge on it. I looked at a LOT of different sources, and they were literally exactly the same from one place to another - with the exception of price.
Filled the plug and socket with silicone grease, plugged 'em in and haven't looked back. Don't have to... There's a blind spot sensor there!
(kidding... I always use blinkers, mirrors, and shoulder glances prior to lane changes)
Last edited by rapidoxidation; Dec 19, 2024 at 04:40 PM.
Can you advise how to seal the plug after its plugged in? Do i just seal it off with silicone after its plugged in and working?
It's easy... use automotive RTV silicone sealant generously around wires where they penetrate into the connector rear. Done!
You could seal where the male connector end meats female end... personally I did not. There is a ribbed seal in there that works well.
Soaking pins into a bed of silicone grease: I do not.
I keep silicone (grease or sealant) away from Mercedes electrical connections.
Silicone is dielectric you don't want to interfere with normal connectivity.
(Silicone gel can be beneficial to protect heavy duty connections that can establish contact. Here females springiness is light duty).
Last edited by CaliBenzDriver; Dec 19, 2024 at 08:54 PM.
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Slideshow: A one-of-one U.S.-spec Mercedes-Benz SLR McLaren Roadster became even rarer after a factory-backed transformation at McLaren's headquarters.
