Thanks simplySLK, I did a search from this forum and found spacer/electrical connector plug is common problem. Will call dealer today for part to fix soon. It looks like an easy DIY with low cost.Our R170 experts must be recovering after the weekend, hang in there, they will sober up soon!
I just had mine done as a wee job in my local garage because I spotted a leak. There are a few videos on Youtube but if it's not been done before I'd recommend changing the fluid and the filter at the same time. The cause of my leak was the Pilot Bushing (odd name for the connector from the ECU to the transmission) and I noticed it because I looked in the passenger footwell hoping to fit an amplifier before I ventured up north on the Scotland trip. Instead I found ATF that had wicked up the loom from the transmission. Genuine Mercedes Parts (fluid/gasket/filter/sump plug/washers/pilot bushing & a dipstick) cost about £130 and mates rates got the job done for £40. Make sure you clean the pins for the electrical connector with proper contact cleaner (don't use brake cleaner - that stuff will affect insulation and plastics!!) and check the sump for any swarf or metal bits. If you've not got a magnet in the sump I'd recommend getting one and fitting it.This is the best post I have seen so far on fixing this problem. I have an '03 SLK230, that leaked about 16 oz of fluid while in storage over the last 5 months. I checked the pan gasket and it isn't leaking. I have no drain plug, so when I do replace the tranny fluid, I will also put in a pan with a drain plug. I have ordered the Dorman 917-505 Transmission Harness Connector/Adapter Plug $7.12 part on Amazon today. I saw somewhere when researching this before about also replacing the part that this one plugs into. Do I need that also? I can't find that part number again. I have checked Pelican Parts. Any help will be greatly appreciated. Maybe just the one Dorman part will be good enough? I understand that there is little room to work replacing this. Any other tips on this?? Thank You tinySLK.