I recently purchased a 2011 GL450 with about 98k miles. I was about 700 miles into a 1000 mile trip towing a car on a flat trailer and a warning light came on the dash. It is an outline of the vehicle with an upward facing arrow below the chassis with the word "malfunction". I looked through the owner's manual and the only warning picture shown with an upward arrow and "malfunction" has the arrow within the vehicle,

 

That is the airmatic warning that this system is taking too long to pressurize. You’ve likely bought a car that needs attention to one or more of the air suspension components the first place I would start is checking the rear bags for leaks. If they have been leaking for a long time the first thing to burn out is the compressor.

 

I was mistaken, It is the level control malfunction. Do I need to bring to the dealer or is the a way to check? It isn't consistent, but does come on each time I restart after a bit of driving.

 

Yes search airmatic failures on this board. This has been discussed ad nauseam and you’re not the first person to buy a GL that needs everything.

The really good news is that most of this is DIY at a fraction of the cost that a dealer or an independent mechanic will charge you.

 

Thanks, I did do a few searches. Car is currently driving fine, Height adjustment seems to still go up and down with the switch. I was towing when it happened. I plan on the return trip in about 10 days (1000 miles) and had planned to tow a car and trailer with me. Is it possible to keep using for a bit until symptoms begin?

 

symptoms have already begun. You have a bag/bags that are leaking. Compressor is working overtime causing the error.

it may work for 5,000 miles, it may only work for 5. When the compressor goes, you are stuck on bump stocks unless you can find a cheap one at an auto parts store to change on the side of the road…and this cheap unit may last for 5 or 50,000 miles.

same goes for a bag. A bag bursting on you will put you in a bump stop situation awaiting a tow…or worse, lose control with a trailer behind you.

 

Do you have information on the exact error? Or just the dash display?

It is probably the air pump in the process of failing.

The air pump often goes bad because it is working overtime to inflate leaky air bags. Does the vehicle settle down, front or rear, overnight? The air pump also simply has a finite life time.

If you cannot do the work yourself, consider asking around to try to find a mechanic to change the air pump, either putting in the cheapest they can find, used or Chinesium, or a good (AMK manufactured) pump.

If the suspension is not settling overnight, you probably can get away with driving home. Probably.

 

Unlikely while towing a trailer.

I’d swap the rear bags and test the compressor, swap if necessary; now.

 

Car isn’t settling at all. It is getting diagnosed at a specialist on Thursday. Usually, I do a lot of my own work, but this car is my wife’s vehicle and my shop is 1000 midges away!
I appreciate everyone’s comments. Thank you

 

Bad airbags and now possibly a ruined compressor. The rear airbags are relatively cheap and easy to replace. It's a quick DIY.

 

Rear bags require a jack, jackstand and a 10mm stubby wrench to change - in addition to a lug bolt tool, which you have on board.