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Mike,
Selecting the trailer when in reverse should change the lines displayed on the screen and tilt the view down a little to make it easier to hook up to the trailer (see Scargo's post #2 for what it should look like).
Scargo,
I checked and I've got the brake controller connector in the driver's footwell. I don't have the trailer at my house so I'm not sure if everything works, but there is 14.5 VDC at the "+" pin of the connector and ~1.8 VDC at the various pins for the lights. Does yours also deactivate the rear partronic sensors once you connect the trailer? The dealer used the following parts per the invoice:
1x 166-310-01-95 TS TRAILER COUPLING
2x 166-470-01-81 BRACKET
20x 006-997-35-90 LOOM TIE
2x 002-990-53-50 NUT
SHRINK WRAP
7x 006-997-35-90 LOOM TIE
2x 000000-007653 FUSE LINK
1x 000000-007648 FUSE LINK
I just bought the car from the same dealer a few weeks before and was able to negotiate most of the price of the hitch kit and install into the purchase price since I knew I wanted it from the beginning. Basically I've paid for a part of the labor cost to get it installed.
Turn the control knob on console to select icon and push enter. It changes camera angle down to see trailer tongue. I posted a picture at the top of the thread
Mine doesn't have the parktronic sensors, so no help there. I'll have to try the icon to see what it does for me. I an already see the back bumper and hitch ball without any change. The only trailer I tow doesn't weigh 300 lbs, plus a 350 lb Ducati, so I typically just pick up the tongue to hook up.
So it looks like the trailer rear view camera is the only thing not working for me. I was able to connect up to a trailer last night and all the lights function properly and the rear parktronic sensors and active blind spot assist turned off. I wonder if the "necessary software" was an update to the head unit to enable the rear view camera trailer mode? There's a setting in the engineering menu for "RVC Trailer Mode" and mine was already set to "on"; turning it to "off" removed the trailer icon but turning it back on didn't make it function. My other thought is I've read somewhere else someone say that the rear view camera needs to be calibrated when a trailer hitch is added, maybe that could be it.
I would say that the change in the rear camera view is more of a zoom than change in angle. I had no trouble backing up to the trailer tongue in either setting. You would only use it for hooking up
Not quite sure why I didn't find your thread initially, but I am in the process of trying to add an OEM hitch setup to my 2012 ML350 BT. I am slowly getting things added piece by piece. I had initially found that the complete kit wasn't available and started buying the individual parts. I am currently only missing the second wire harness (166-540-44-10), luckly this can still be purchased thru Mercedes. So far, I have spent about $550 for hitch assembly, electrical harness 1 (166-440-70-13), trailer module (246-900-55-01). I made my own brackets for supporting the DEF tank and muffler heat shield. A fellow subscriber was kind enough to post the trailer hitch WIS, which I am trying to digest. I just purchased the vehicle last January and really haven't gotten to drive it much, to it in for a health check after I purchased it and was told that the rear main seal or oil cooler seal was leaking. I successfully made the repair, also cleaned the intake manifolds, due to soot accumulation, and replaced the crankcase vent, which was leaking excess oil (reason for the sticky soot accumulation). I am amazed at the number of things that I found on this car, which only has 86,000 miles. When working on the hitch I found that the rear suspension spring need to be replaced they have both broken near the ends. I also had to fix the rear angle ball connector, which wasn't free to rotated due to corrosion of the ball connector.
I have the mechanical part of the hitch install complete and am starting the install of the electrical harness assembly. I have the trailer SAM module mounted and the cable to the hitch run. The longer cable I started laying out to the F4 fuzz block under the rear seat. I am having trouble with my 110 volt outlet (see the last photo) just in front of the F4 fuzz assembly to released so I pull the carpet back to run the longest cable section to the drivers side of the vehicle. Any other suggestion would be greatly appreciated. I will need to take the car in for the software update for the hitch addition. Will there be any issues driving the car with the wire updates before the software update?
Adding OEM hitch equipment to my 2012 ML350 Bluetec
Well, I am still working to add the wiring to support my OEM trailer hitch. I was able to acquire the physical hitch, foam bumper spacer, wire harness to SAM control box, SAM control box itself, and OEM car integration wire harness. I have completed to routing of this harness to the different parts of the car. Part of the harness connects to the (F4) fuse block under the rear seat, another section follows existing cables just behind the rear seat to the driver's side and then forward to the driver foot well. There is a single wire that goes forward to the passenger's front foot well.
I am currently trying to install the single wire (black/white striped) at the passenger's foot well that connect into (N10) connection block/48 pin connector. Currently I haven't succeeded in getting the cover off of the (N10) connector block so I can add the wire to the container, this is shown on page 7 of the retrofit trailer hitch wiring harness WIS, (AN31.19-P-8100-05GQ). The cover cannot be removed because of how close it is to the heat air fan unit. Also, may try and remove the whole block, but I am not sure that is possible either?
Well over the last couple of days I have been working on routing the wire harness (1665404410) that comes from the rear trailer module SAM unit. I had gotten a quote from our local Mercedes dealer for finishing the wire installation and they quoted ( $3000 ) not sure if they really understood the work that needing to be completed. I have completed the running of wires under the carpet to the drivers side and passenger's foot well. It took a bit of finagling, actually a lot, to get the cover off of the (N10) connector module in the passenger foot well, to access the 48 pin connector for adding the (black/white line) wire to the 48 pin connector. I actually removed the glove box to ease getting access the connection block. I finished the ( sw/ws) wire install and moved on to last wire connection to the (F4) fuse block. I successfully unmounted the fuse block and am ready to start add the power supply wires of the trailer wire harness. Ran out of time today and will try and finish the install tomorrow. I believe my slow progress is in part due to not knowing how to take things apart. It is a continuous learning process
FINAL STAGE OF ADDING AN OEM TRALER HITCH TO MY 2012 ML350
I have all mechanical items mounted and all the cable wire harnesses run to their proper locations in the car as shown in the picture below. I have scheduled at the local MB dealer to get the software updated, hopefully all goes well. See the what I completed thus far. I would like to know what cable 22.2 is for, does this connect to the electric brake controller or is there an existing Mercedes cable that it connects to? If there is one I have looked at the two previously posted, but have been unable to locate it.
Yes its for use with a brake controller, Tekonsha, Reese and other's make adapters for there units to connect to 22.2
If it is there it can be hard to find, mine was tucked under the floor mate, comes with the 550 options
Thank you for adding to the thread, our current trailer doesn't have brakes, so do not need a brake controller at this time. Just wanted to make sure that this part of the cable did connect to an existing cable in the car. Since I ran the cable myself, I know where it is when it comes time to add a brake controller. Most of the other connection were pretty straight forward and took my time. Hopefully I didn't make any mistakes and the software update goes ok when I take it in toward the end of the month.
I got the software updated for the added OEM trailer hitch addition to my 2012 ML350 BT. There were no issues with the update on adding the update, although I will need to do some checking to see if everything works as it should when I connect my trailer to the car. Bill for the update was $224.4, $174.00 for the labor, $34.80 for shop supplies/hazard waste disposal, and 15.66 state sales tax ( not sure how a software update needs shop supplies or hazard waste disposal fees ). Hopefully everything goes well when I go to use it, I did see the tow trailer Icon when I put the car in reverse.
Last edited by rmassmann; 05-26-2022 at 08:37 PM.
Reason: add missing txt
Trying to get rear view camera to enhanced view after trailer software update
Well I got the software update back in may and the car recognizes when a trailer is connected, but when I select the trailer icon on push to accept the icon darkens but then goes back to light. I went back to the dealership where the update was done, and they are saying I will not get the modified view since it takes more than was currently installed. I do not really believe that. The service person I talked with said to drop the car of the next day and they would review it, but when I came back, they balked and said that, that screen view is not available unless it came from the factory installed with all the special options for heavy towing, like heavy duty radiator fan, high-capacity fuel tank and other things. So, I am going to keep searching to see if it is a software bit change or it is unavailable for my car model and year? I have attached a video of the display screen when I try and select the trailer option.
been some time since I change any thing ( see post3 in the king) after you make a change back out until you see the END option select it then it should ask for a restart, if not try again.
I'll make some changed this weekend and write all the steps down
Had my 2012 ML350 in last Friday at the Mercedes dealer for the trunk water intrusion recall, at the same I asked them to recheck the engineering mode setting, after getting the car back, they said they were unsuccessful in finding or checking the parameter, I had even given them the printout from your post. so I guess I will have to do it myself?
Had my 2012 ML350 in last Friday at the Mercedes dealer for the trunk water intrusion recall, at the same I asked them to recheck the engineering mode setting, after getting the car back, they said they were unsuccessful in finding or checking the parameter, I had even given them the printout from your post. so I guess I will have to do it myself?
Hi. Thank you for your post. I'm doing this same thing now and on the part with connecting all of the wiring. I'm curious about whether or not your car acts differently when connected to a trailer. More specifically, when the coding was done, did it change the shift patterns in the transmission? Do you get the anti sway control? This may be hard to determine.
Sorry I haven't gone beyond fixing the wiring on my small camper and small boat trailer. Haven't driven car towing either trailer yet. Was hoping to get a larger trailer to tow but haven't found one yet.
05-15-2019, 11:14 PM
Adding OEM hitch equipment to my 2012 ML350 Bluetec
