Temporary Airmatic malfunction after wash
Thread Starter
Junior Member
Joined: Dec 2024
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Temporary Airmatic malfunction after wash
Hello guys!
After washing my GL350, I get a temporary Airmatic malfunction message. It usually disappears by the next day. Probably moisture affecting some cables or sensors. I don’t spray underneath the car, so probably around the wheel wells?
Anyone experienced the same issue and can guide me in the troubleshooting?
Thanks in advance!
After washing my GL350, I get a temporary Airmatic malfunction message. It usually disappears by the next day. Probably moisture affecting some cables or sensors. I don’t spray underneath the car, so probably around the wheel wells?
Anyone experienced the same issue and can guide me in the troubleshooting?
Thanks in advance!
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NGL450 w/EORP, S550
It’s not temporary you have some kind of malfunction. Generally, that one will come on when the pressure in the central reservoir isn’t what the system commands it to be.
And the reason for that is that the compressor isn’t filling the central reservoir.
Why?
The compressor is either not being turned on
Or
The compressor is unable to output the required pressure.
And the reason for that is that the compressor isn’t filling the central reservoir.
Why?
The compressor is either not being turned on
Or
The compressor is unable to output the required pressure.
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From: NE OHIO
1998 SL500,2011 GL550,2009 ML350,past 1995 E320 Cabrio ,2005 ML500,2006 ML500,1996 SL500,1972 280SEL
How many times
Hello guys!
After washing my GL350, I get a temporary Airmatic malfunction message. It usually disappears by the next day. Probably moisture affecting some cables or sensors. I don’t spray underneath the car, so probably around the wheel wells?
Anyone experienced the same issue and can guide me in the troubleshooting?
Thanks in advance!
After washing my GL350, I get a temporary Airmatic malfunction message. It usually disappears by the next day. Probably moisture affecting some cables or sensors. I don’t spray underneath the car, so probably around the wheel wells?
Anyone experienced the same issue and can guide me in the troubleshooting?
Thanks in advance!
You might have to take the wheel wells out and examine all the connections looking for water etc… of course during the error would be best… the wheel wells are not that big of a deal to remove . Keep us posted.
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From: Melbourne, Australia
2010 ML550 VIN WDC1641722A564750, 2010 B180
The malfunctyion message is also linked to the compressor overheating. Id say thats yoir problem. It heats up, stops and the cools down again, hence why it works the next day for you. Most likley you have a leak and the compressor is working overtime, which they aret designed to do. There just there to manitain pressure not conitually keep the airnags full because of a leak. Soapy water test now hilst your compressor still works to find the leak, fix that and probably a new compressor in the short term. Test with soapy water with car on highest setting and load on the wheels. Dont get under the car whatever you do - if it falls it will kill you.
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From: Allentown, PA
'08 GL 320 CDI
If it ONLY happens after washing the car, I'd say you're on the right track. I honestly don't know a ton about the specific wiring of the Airmatic system... but I'd pull the wheel well liner out and just inspect really closely. The compressor/valve block is pretty well protected in there, but it seems like a good place to start. Hopefully something is blatantly obvious 
Now, if you wash your car every day, then that changes things and you're back to what was said above. But if you drive the car for many days in between washing with no issues, it sounds like the water is the key variable.
Now, if you wash your car every day, then that changes things and you're back to what was said above. But if you drive the car for many days in between washing with no issues, it sounds like the water is the key variable.
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Mercedes gl450
If it ONLY happens after washing the car, I'd say you're on the right track. I honestly don't know a ton about the specific wiring of the Airmatic system... but I'd pull the wheel well liner out and just inspect really closely. The compressor/valve block is pretty well protected in there, but it seems like a good place to start. Hopefully something is blatantly obvious
Now, if you wash your car every day, then that changes things and you're back to what was said above. But if you drive the car for many days in between washing with no issues, it sounds like the water is the key variable.
Now, if you wash your car every day, then that changes things and you're back to what was said above. But if you drive the car for many days in between washing with no issues, it sounds like the water is the key variable.
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Hey guys and thanks a lot for taking time to respond to my thread, and sorry for my late action to this...
I still have the problem and yes, it always happens after washing the car and yes, it always disappears again after a day or so. I've now bought a good scanner and the fault code is:
5353 A9/1y1 (AIRmatic pressure release valve) : Ground cable Short circuit to GND.
So I've found a cable behind the grille, leading towards the compressor, that's completely soaked in water after I've washed the car or after some mild rain. When I have the time, I need to tear down the front / front right side to further troubleshoot this cable and the connector to the compressor / pressure release valve.
Question: Can't find anyone else on the internet with this exact fault code (can find some with 5350, but not 5353) so if anyone here is experienced or knows something about this, I'd be extremely grateful for advice / hints / tips..
Thanks again!
I still have the problem and yes, it always happens after washing the car and yes, it always disappears again after a day or so. I've now bought a good scanner and the fault code is:
5353 A9/1y1 (AIRmatic pressure release valve) : Ground cable Short circuit to GND.
So I've found a cable behind the grille, leading towards the compressor, that's completely soaked in water after I've washed the car or after some mild rain. When I have the time, I need to tear down the front / front right side to further troubleshoot this cable and the connector to the compressor / pressure release valve.
Question: Can't find anyone else on the internet with this exact fault code (can find some with 5350, but not 5353) so if anyone here is experienced or knows something about this, I'd be extremely grateful for advice / hints / tips..
Thanks again!
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MBWorld Fanatic!
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NGL450 w/EORP, S550
Hey guys and thanks a lot for taking time to respond to my thread, and sorry for my late action to this...
I still have the problem and yes, it always happens after washing the car and yes, it always disappears again after a day or so. I've now bought a good scanner and the fault code is:
5353 A9/1y1 (AIRmatic pressure release valve) : Ground cable Short circuit to GND.
So I've found a cable behind the grille, leading towards the compressor, that's completely soaked in water after I've washed the car or after some mild rain. When I have the time, I need to tear down the front / front right side to further troubleshoot this cable and the connector to the compressor / pressure release valve.
Question: Can't find anyone else on the internet with this exact fault code (can find some with 5350, but not 5353) so if anyone here is experienced or knows something about this, I'd be extremely grateful for advice / hints / tips..
Thanks again!
I still have the problem and yes, it always happens after washing the car and yes, it always disappears again after a day or so. I've now bought a good scanner and the fault code is:
5353 A9/1y1 (AIRmatic pressure release valve) : Ground cable Short circuit to GND.
So I've found a cable behind the grille, leading towards the compressor, that's completely soaked in water after I've washed the car or after some mild rain. When I have the time, I need to tear down the front / front right side to further troubleshoot this cable and the connector to the compressor / pressure release valve.
Question: Can't find anyone else on the internet with this exact fault code (can find some with 5350, but not 5353) so if anyone here is experienced or knows something about this, I'd be extremely grateful for advice / hints / tips..
Thanks again!
The fix could be a simple as tightening the ground and spraying some electrical connector spray on it.
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Thread Starter
Junior Member
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no, you found it. If you look up that ground location (a9/1y1) in WIS (subscription needed) that would be the cable that’s getting wet. And if the power to the air distribution valve can’t get to ground then the air distribution valve ain’t doing air distribution things.
The fix could be a simple as tightening the ground and spraying some electrical connector spray on it.
The fix could be a simple as tightening the ground and spraying some electrical connector spray on it.
BUT - then I read that the W2 Ground is also used for the left/right horn and the cable to the horns were soaking wet and was placed very badly behind the grille, on a metal bar with a groove where water collects, allowing even small amounts of water to accumulate into a larger pool. When driving, the airflow causes this water buildup to blow onto the wiring for the horn.
Since it shares ground with the Airmatic pressure release valve, I assumed the issue was related to that and that I had never noticed the horn not working (since I don’t drive around honking all the time). So, I have now secured the horn cable so that it doesn’t rest against the metal bar, washed the car, driven home – and no issues. So far, so good!
Hopefully, this simple fix is permanent, and that others looking for the same issue with 5353 A9 / 1y1 in the future will find this thread!
Last edited by GL350_Sweden; Mar 16, 2025 at 01:52 PM.
MBWorld Fanatic!
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From: Melbourne, Australia
2010 ML550 VIN WDC1641722A564750, 2010 B180
I can't answer your question regarding the fault code but can suggest you can remove the inner wheel well liner and turn the wheel inwards or better still, take the wheel off. This will give you more then enough room to access the compressor. Change the air compressor air filter (sits at the top of thr wheel arch) whilst you're there
MBWorld Fanatic!
Joined: Jun 2014
Posts: 1,086
Likes: 443
From: Melbourne, Australia
2010 ML550 VIN WDC1641722A564750, 2010 B180
Thread Starter
Junior Member
Joined: Dec 2024
Posts: 20
Likes: 1
I can't answer your question regarding the fault code but can suggest you can remove the inner wheel well liner and turn the wheel inwards or better still, take the wheel off. This will give you more then enough room to access the compressor. Change the air compressor air filter (sits at the top of thr wheel arch) whilst you're there
The issue was actually with the horn cables behind the grille getting wet after a wash. I’ve already posted the solution in my previous comment.
