EWT

After watching a video from LegitStreetCars (great channel with a lot of older MB repair content) about repairing water-logged electronic modules in a 7 Series:

I decided to give it a try on my front SAM that got wet a couple of years ago. After getting wet, the right front marker light and the ashtray light stayed on full-time, which I "fixed" by disconnecting the bulbs, so the battery wouldn't get run down, but the missing marker light triggered a warning on the dash that had to be dismissed at every startup.

Since the module sits under the front seat, removal requires taking out both the main and aux batteries, removing six electrical connections and a couple of torx screws holding the SAM down. Once out of the car, the cover pops off after releasing 3 clips on both sides. My SAM had a little rust around one of the connectors, but the connector pins were in good condition. The circuit board had evidence of water intrusion like the ones in the video and corrosion on some of the legs of the electronic components on the board. I didn't have the CRC contact cleaner used in the video, but had some BW-100 on hand: After spraying the corroded spots with contact cleaner and brushing gently with a toothbrush, I put the SAM back in the car, and all is fixed. If you're experiencing SAM problems related to water intrusion, it might be worth picking up a can of contact cleaner before buying a new one and having it "married" to the vehicle.

I forgot to take a picture pre-cleaning, but a picture of the inside of the SAM after cleaning (you can still see a little residue at the bottom of the board):

2008 GL front SAM

Max Blast

Nice! I think the errant water bottle / juice box getting squashed by the seat kills more front Sams than we think - typically, it occurs via a clogged cabin air filter box drain but the stain and following corrosion is the same regardless.

Unless it’s Cola - then you’re looking for a new Sam. That stuff will rot anything it touches.