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Dynamic Seat Function Completely Disappeared from Comand Control Unit
So all my options for dynamic seats have completely disappeared from my Comand interface on my 2007 S600.
I DID have my Comand programmed to turn on Aux in right before this went away, so while I think it might have something to do with it, both the company that programmed the AUX on and another person I know that is very familiar with this model car said that AUX being activated in the command has NOTHING to do with seat functions. I have made a video showing exactly what the issue is here. Has anyone else had this issue? If so any help is greatly appreciated!
Did you check to see if the passenger side dynamic seat is working? If it is, then I'd guess you have a blown bladder in the driver seat or a bad connection under the seat. If neither are working, then the issue is likely in the COMAND head unit that you were messing with to install that aux out wire.
My S550 2008 just did the exact same thing!!!! Did you find a fix for it?
I have a 2008. My drivers seat works at times in terms of filling the bidders and at other times, does not. When I start the car, the lumber is ALWAYS on a different setting. I reset, go to get a coffee, shut off the car and it happens again. EVERY time. Software? Settings? Loose connection under seat? (Is that hard to get to)? I would LOVE to fix this with out spending $1,000,000 dollars on it. Love the car but truth be told, I sense that these seats could have been designed and built a bit better. They say that the older series were what they called "over engineered." I sense that the seats were not.
I've got the same issue with my 2008 S65. When I press the seat button on the console, the Lumbar setting comes up but I can't do anything at all. I can tell it to adjust the lumbar but it immediately goes back to zero. And there's no setting for any other seat function.
My daughter tells me that the passenger seat is "hugging" her around curves so I guess something is working. Could this be a bad connection? A bad bladder?
Update: I swapped the control module from the passenger's side to the driver's side. Now the driver's Drive-Dynamic feature works but the passenger's doesn't. This was an easy swap - the two units are identical and snap right in. Directions below.
The fact that this worked is really good news! The bladders and pump work, the wiring isn't broken, it's likely just the control unit that went bad. So I've ordered a replacement (used) from eBay ($39 delivered). My original was part number 221 870 21 92, the replacement is 221 870 91 86. I might have bought a rear seat unit accidentally. I hope it works but I picked a seller that accepts returns if it doesn't!
Here's how to remove or install these control units:
Unscrew 2x Torx screws at the base of the seat back and pull firmly downward to remove.
Remove the four connectors left-to-right. The first uses a simple tab, the rest have a locking lever (tan on the second black connector in the photo below).
Press the levers on both sides of the control module and slide it up to remove it.
Assembly is the reverse of disassembly. The driver and passenger side units are identical and no programming is needed.
Another update: I bought a replacement (used) seat module from eBay and replaced the known-bad module but the problem still exists. Although both seats now have the Drive-Dynamic function, the COMMAND only ever shows the Lumbar adjustment (shown below) and even this does not function.
Perhaps it's a coding issue. My next step is to take the car to the Mercedes-Benz dealer to get it on the Star/Xentry system to check everything for codes. While I'm there I'll be activating the (existing) Aux Input as well.
It appears that the head unit is not original, and the DVD changer is definitely not original. Whoever replaced the DVD unit didn't snap the cover on correctly and the white sticker doesn't line up. And I know that the hard disk drive in the COMMAND had been removed because someone lost the screws! So perhaps this new unit was never coded properly for the car. This might even be the reason for the reverse camera not working.
08-22-2017, 12:44 PM
