Air Compressor Self Test Question

[Costal_Cat]

Where do you live?

My Pontiacs both have a load leveling suspension with the air compressor. They almost always come on with the key for 4 seconds and you can hear the valve open briefly (1.5 sec) too. Why sometimes not? I don't know, never bothered to look into it.

Hi, @swathdiver I live in NC on the coast outside of Morehead City. I am perplexed at this point. What you and @Doubeleive state is what was happening until after I went for the first ride with the new shocks. I filled up with Gas and then it stopped doing the check. That is why I did the trailer test and such. This weekend I had the kids loaded up and about 30 seconds after start up the compressor kicked on and leveled it up. But still not precheck anymore...

 

[Costal_Cat]

I have owned mine since 98k and never once heard it kick on. I have also towed 4500 pounds with zero zag and perfect level. Both shocks hold air and no issue with ride quality .

Seem that is like this with my buddies 14 as well, @97audia4. He was wondering wtf I was talking about. He stated his only did this when his boat was on the truck or he had a load in. I just don't get because otherwise, it does just like it should with adding air and releasing air. Maybe I am jumping at shadows here but it was certainly doing it before the new shocks and when I first put the new ones on

 

[Doubeleive]

there was a tsb that another person posted recently that described some issue's and fixes for the air suspension and one of them was the system would only occasionally self-check and basically it said it would only self check if it sat for a extended of time but gave no other explanation and just completely contradicts what it is supposed to do. so? I don't know other than I replaced mine and it self test's every time now like it should each time I cycle the key regardless if it has been 10 seconds or 5 days or anything.

 

[swathdiver]

Hi, @swathdiver I live in NC on the coast outside of Morehead City. I am perplexed at this point. What you and @Doubeleive state is what was happening until after I went for the first ride with the new shocks. I filled up with Gas and then it stopped doing the check. That is why I did the trailer test and such. This weekend I had the kids loaded up and about 30 seconds after start up the compressor kicked on and leveled it up. But still not precheck anymore...

If you were closer I'd hook up the Tech2 and have a look. Beautiful area, used to spend a lot of time in Wilmington and Wrightsville Beach.

 

[Costal_Cat]

If you were closer I'd hook up the Tech2 and have a look. Beautiful area, used to spend a lot of time in Wilmington and Wrightsville Beach.

Thanks for the offer... I'm going to keep playing with it and I may just end up getting one myself after the holiday.. a couple of other items on the list first ...
Yeah went to school at UNCW moved up here to Emerald Isle for a little more peace and quiet... Wilmington was great though .....

 

[Costal_Cat]

Ok update here on the Self Check

It is working on startup now. What did I do... Not much the truck has been working fine I have been doing a lot of towing over the last couple of months and the leveling system continues to work as it should since changing out the shocks and compressor. Today I took out the spare in prep for changing the diff oil and thought I'm going to disconnect the air hoses and let the shock's air out and see what happens. So I did that and the self-test kicked on and added air to the deflated shock. I thought that perhaps the bulletin discussed in this thread was correct and once aired back to the base state it would be silent as it has been since Nov. Well, I have tried 10 x's and every time the self-test kicks in as it should. Why ??? No Idea but it is now working go figure.....

 

[avalonandl]

TTT- reading up on this....

 

[ieastsidechevyrider]

Ok update here on the Self Check

It is working on startup now. What did I do... Not much the truck has been working fine I have been doing a lot of towing over the last couple of months and the leveling system continues to work as it should since changing out the shocks and compressor. Today I took out the spare in prep for changing the diff oil and thought I'm going to disconnect the air hoses and let the shock's air out and see what happens. So I did that and the self-test kicked on and added air to the deflated shock. I thought that perhaps the bulletin discussed in this thread was correct and once aired back to the base state it would be silent as it has been since Nov. Well, I have tried 10 x's and every time the self-test kicks in as it should. Why ??? No Idea but it is now working go figure.....

So all you did was disconnect the air hoses from each shock? Did you remove any fuses prior to doing so, or did you just disconnect each air line? Was the truck on and running when you did this, or did you disconnect the air lines when the truck was powered off? Please help, I'm having the same problem and the dealership was no help.

 

[Davisr32]

Well I joined the club now as well. Not sure if anyone ever figured this out.

2013 LTZ w/Max Trailering, replaced air compressor with a Dorman as the old one you could easily tell the bearings were going bad based on the sound but was still working. It would do the self check/fill on most startups but not always, especially if too close together.

With the Dorman, it kicked right on once I plugged it in and proceeded to run on the first startup. After that though seems to only run as needed. Disconnected air hoses and power line and the shocks are clearly holding air just fine and it re fills each time.

I spoke with Dorman and they don’t have any documentation about the self test on startup but said if it’s level, holding air and kicking on with extra weight it should be fine. Added that it has a lifetime warranty, so if it does stop working it’s covered.

Found this thread and the service bulletin which is quite interesting. Based on that and the fact the old pump didn’t always run, I am going to chalk it up as an oddity at this point and run it as is until something changes or I can find better info.