res94025

I recently managed to find a 2010 GL550 with only 40k miles and the only option it didn't have was the trailer towing package. I ordered the OEM hitch and harness from MB and have completed the install of the hitch itself. All pretty straightforward and took about two hours. I have the OEM harness run into the rear quarter by the rear fuse block and understand all of the connections - but I'm trying to figure out how to best access the SAM unit in this area. It appears to be under the subwoofer and I wonder if I need to remove the radio amp and subwoofer to access the port for the trailer connection - or is there some easier option? I've seen someone state that the best approach is to remove the air filter panel on the exterior of the vehicle to access the SAM, but I'm concerned about long term impact on the water seal around the vent as obviously this is not an area where one wants any water intrusion to the electronics. I've searched the forum and found lots of discussion about trailer hitch installs - but haven't seen anyone ask/address this specific issue about best way to access the SAM. I figure better to ask the folks here before I embark on trying to figure it all out myself ...

Edit: Never mind. Went back out and stared at the car for a moment and explored that rear air vent. Popped off very easy and gave me perfect access to the plug I needed on the SAM. All wired up now and the only remaining project is to reinstall the bumper.

fabbrisd1

Interesting post - once you have everything zipped up and working - please post back your success.

I "think" you might need a different SAM with the tow package - so that's why I say post back with your final success for others to follow