My 2009 H2 SUV is equipped with Rear Air Bags and Auto Ride height. I like it. Not interested into going with a spring replacement. Anywho, I came out today and the 2 was squated all the way down on the bags. I hit the Up switch and she went all the way up to the extra 2" ride Height. The indicator light went out and all was good.

So I hit the button again and the *** end went back to normal ride height. This happen about 2 weeks ago. I came out of the house and it was down, I did the same thing and pumped it up. All good. To day after I reset it, I scanned for codes. There were none.

I did do some reading in the owner's manual and it did mention that if the rear cargo area has to much weight the system will not operate. I did have a bag replaced back in 2010 after off roading and picking up some sand around the bag which made a small puncture. Since then all as been good. I do have a lot of off road gear and weight in the rear cargo area. I wonder what's going on?

Not to familiar with the compressor unit. So Not sure if it is venting air. Seems like the driver side is slightly lower when she hits bottom. But both sides go down.

Any Ideas?

 

Mark - I went through this on my 2008 with air ride. One day I came out and it was down. If you start it and close the doors, it should automatically re-inflate the airbags. I was able to do this for two years, until one day it just would not re-inflate.

You can search the forum as there are many posts on this issue. Here is a thread where I had my compressor rebuilt

I believe @oceanbrave and @bronxteck and @MixManSC have gone through these issues. But, here are some initial steps...

• Rear Suspension Air Bags - you or your dealer can do a soapy water test to see if one or both are leaking. IMHO probability increases that this is the issue if you park outside with wide temperature swings, or have high mileage on the vehicle. The soapy water test is a common test that all GM dealers or your local shop can perform and they usually need you to keep the vehicle there overnight for the test. If a leak is found and you ignore it and continue to use the vehicle and repressurize the system, eventually you will burn out the compressor, which is unobtanium... don't do it. IF the airbags are your problem you are lucky and dodged a bullet. Note, a dealer will automatically want to replace the suspension airbags just to rule them out. You can DIY it, and there are a couple posts on that. There are a couple YouTube videos on it as well and they kinda make it look easy.
• Air hoses - you or your dealer can do a soapy water test to see if any of these are leaking - typically where they attach to the air suspension or to the compressor. This is a common test that all GM dealers or your local shop can perform. Air hoses are no longer available and must be custom cut. This thread has good info on how to do this.
• Ride Height Sensors - It is possible that you have a broken one or that something has happened to them -- you should be able to visually inspect them.
• If you have a Tech2 you can check the codes for a compressor issue. This is a common test that all GM dealers can perform to narrow the problem down. My experience is that most mechanics just are not familiar with vehicles this old, and even if they have the codes, they don't know what to do. My local GM dealer struggled.
• If you have a compressor issue, there is nothing your GM dealer can do. These compressors are no longer available. There are several threads with guys troubleshooting and rebuilding, or replacing with a used unit off eBay. The most common culprit is the level control solenoid on the compressor which either needs to be rebuilt or replaced with similar parts. The compressor can also burn out IF the air bags have leaks and it has to constantly refill them. If you fix your compressor, you must get the air bags replaced even if they have no leaks. Compressors are no longer available anywhere and must be salvaged and rebuilt.

Start at the beginning and let us know your progress!

 

Thanks Brunob00,
I used my cheapy scan tool which showed no codes next week I will be at my local shop that does my oil and general maintenance on the H2. He has experience replacing bags and Comp units on GM rigs. But more important he has one of those Bazillion Dollar Snap On Scan Tools and also the Top of the Line Autel Scan tool.
He his going to run a scan and see what he comes up with.

This morning I went out and the H2 was at normal ride height. It's been like this for about three days after the squat and me pumping it up. So I fired the H2 up and went out and closed the door and put my ear up against the *** end and heard the Comp make some clicking sounds (As if it was dumping air) for a few seconds. Prior to me doing that I removed about 50Lbs of chain and other off road gack from the rear.

So when it's in next week will scan it and see what's up. I think I will replace the bags anyhow. I need to shop for some good ones. What's your choice... Aftermarket or GM bags?

He said about three months ago he had replace a complete comp assembly in a GM something ..not a Hummer. But he has done this work before. Also , I found a GM complet original Comp Assembly on line in the UK... Bit the Price is $$$$$$$ Nuts

https://p38spares.com/fr/hummer/234-...989000025.html

Also this ..but out of stock... Call for more info...
https://www.invasionautoproducts.com/08huh2supu25.html

And this one...No stock and will not be getting anymore.

https://rebuildmastertech.com/hummer...jN7Ev5Plesx94V

Back in 2010 I did have the driverside level sensor on the swing arm replaced and the Air Ride system reprogramed. It's not simply a swap of parts in general There is I believe always programing involved. All the old guard has now retired and Gen Z has moved in. That's a good thing bit not for the old stuff.

Regards: Mark R

 

I am familiar with the last two... and you only need to go down this path if your compressor is actually showing codes...

• Invasion says they can repair your existing unit. I was not overly impressed, but I would give them a call and see what they say.
• I called RMT, and they no longer rebuild the Hummer compressors

The only other path for compressor parts is ebay - but you need to be clear on the part number you need. I always see auctions that say 03-09... and there were like 4 different designs across those years.

 

[QUOTE=Brunob00;418621]I am familiar with the last two... and you only need to go down this path if your compressor is actually showing codes...

• Invasion says they can repair your existing unit. I was not overly impressed, but I would give them a call and see what they say.
• I called RMT, and they no longer rebuild the Hummer compressors

The only other path for compressor parts is ebay - but you need to be clear on the part number you need. I always see auctions that say 03-09... and there were like 4 different designs across those years.[/QUOT

Yeah Thanks Bruno00..
It would have been nice if they put a Comp Run Light in the Instrument panel or in a separate area so you could tell when the compressor was running. The only way to know that is when you push the up or down Button for the Lift system.

This would tell you if it was running all the time during a leak.