I did some searching but did not find any recent info on how the 4matic should work. Indications are that the brakes should be applied to any spinning wheel to allow power to route to the one/s that are not turning?

The situation;
2002 e class 4matic that slid off our driveway into the woods. It had gotten stuck on the steep section so swmbo parked it. Then with no one in it, it slid off the driveway into the woods.

I dug out the snow around the wheels and tried to move it. It didn't go anywhere and the rear drivers wheel was spinning - none of the others were spinning, and one fron wheel was on the pavement. With the wheel spinning the triangle lit up on the dash but I didn't have any evidence of brakes being applied to spinning wheels so the ones not spinning could try to turn.

No malfunctions flashed up on the dash.

So my question is should the 4matic have allowed one wheel to spin? I know that the car may not have been able to pull itself out of the situation it wound up in but it seems like the 4matic is not necessarily working as it should.

Any easy way to test the proper functioning of the system. Car is still under the extended warranty.

Thanks for any help.
Paul

I believe the part of the system that uses the brakes to combat wheelspin is the traction control (the acronym is ASC I think). This is what the yellow triangle on the dash will light up for. The brakes are also used on an individual wheel basis by the ESP system when you are moving down the road and you start to slide out of control. The 4Matic system works differently when transferring power from front to back. That is where your transfer case/centre differential comes into play.

If you're under warranty I'd take it back to the dealer.

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Jonathan

2011 Mazda2
2000 E320 4Matic Wagon
1994 C280 (retired)

The 4-matic system on that car is just like the 4-ETS system on the ML's.
100% electronic. if any wheel spins the traction system SHOULD intervene & apply the brakes on the spinning wheel.

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Sounds like its not operational....from what I've read, the sysem will halt all the wheels without traction if necessary and give all power to the one that does.

In a test in a magazine I was reading the ML320 they were testing managed to scale a real steep icy/snowy slope dragging itself up with only one front tire that had traction! amazing.

I'm guessing your system isn't working as the wheel shouldn't have spun with no intervention....

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Thanks for all the input. Kind of matches with what I thought should happen.

I will make an appointment with the dealer.

In case you want to see I am attaching a copy of a picture of how the car was stuck. The car slid backwards, and when the two rear wheels went off it spun the front around. No one was in the car at the time

You can also see that the right front wheel was on the pavement.
No damage to anything (luckily no big trees in the path it followed).

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