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AIRMATIC DEFLATED BUT NO DTCs? PLEASE HELP THE VILLAGE IDIOT!!
Airmatic stopped working after I improperly loaded a trailer and had too much weight on the tongue, but prior to that worked fine.
The 40A fuse is good. The system is low on air but not entirely collapsed and the diagnostics shows no DTCs, Pulled air compressor and it runs as long as I want, yet it won't run for more than a second when it's in the car.
I would suspect a burned out compressor from too-long run times, but the motor still runs. I'd also suspect a bad relay. I haven't checked it, but there sure is a heckuva lot of clicking going on up front.
check that you can actually pull the 40 amp maxi fuses. Sometimes under heavy load, the spade connectors will burn through and fuse with the fuse box. This creates a no power to the compressor condition in the car, while it works fine on the bench or hooked up to 12 V.
Nothing in your DTC shows anything of concern other than the central pressure being 4.8 bar.
But why won't the compressor run an appropriate amount of time to correct the low system pressure? It does run on initial cue (door opening, occupying seats) but only for a second.
Max Blast, you were right: the issue turned out to be the compressor (<$100 on Amazon), so everything's working correctly now - I hope.
Isn't it curious that no DTC was generated for a defective compressor, or is one supposed to deduce that from the low system pressure?
In any event, thanks for the assist!
The two codes you would see for a failed compressor are:
1. Time to refill central reservoir pressure too long.
2. Pressure in central reservoir too low.
Depending upon how failed your compressor is, you might not even see 1. A very weak compressor can still get to the 16 bar in 40 seconds threshold if it’s just on the edge of failing. And then same for two it’ll build pressure but it’ll just take an inordinate amount of run time to do it.
A seized compressor, or a no power to the compressor condition, will trigger 1.
immediately after the Central pressure reservoir has been depleted to below I think it’s 12 bar and it has failed to be pumped back up again to 16. When the pressure falls below 12 bar (iirc) 2. Triggers immediately.
but if you’re not using an actual Mercedes scan tool, then I bring seeing anything into question… your tool might not be able to read it. Although, it looks pretty high speed.
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Slideshow: A one-of-one U.S.-spec Mercedes-Benz SLR McLaren Roadster became even rarer after a factory-backed transformation at McLaren's headquarters.
MANY THANKS!
