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New EXT Owner

Truck came with a trailer brake installed and it was working, so good to go there.

The church trailer will only get towed once a year for 5 miles max, so this is fine. The bigger concern is what the Jeep on the uhaul trailer will be like because there will be no load distribution or antisway available there. Hopefully when I do that I will have the air ride/load leveling working properly and that will sort that out. My friend towed his Jeep with a Yukon XL - same year, same platform, pretty much the same weight towed - and it was a dream for him so there's every reason to believe it will be fine.

The camper towed perfectly, and that is going to be what's towed the most. I do have a load leveling/anti sway hitch for it, but it's nicer not to use it. I'll probably do the first trip without it to see how it goes but I towed it for maybe 5 miles at 65-70 and barely knew it was back there, so I think it's OK as-is.
 
you could have just uploaded pics to your FREE album we have for every member under MEDIA tab.
then post link
 
There was a 1mb limit per photo and it was too difficult to try to shrink them

Now that you are a full member, you should see an "insert image" button on the toolbar when composing your posts.

It is a simple matter to determine where you want the picture to show in your post, click that button and find the picture you want to insert and done.

I prefer the way my posts look using that method than linking to a stored picture.

I don't care to go off-post to view a picture in a post.

But, that's just me.
 
Ahh.. I remember those days in my grandfathers old k1500. I really wish i was anywhere near old enough when they sold that truck. Loved the look of it.
 
Just thought you'd like to know that the heated seats are working now. The connection under the seat came undone.

I have be reading through the 25 page auto leveling post because I can't get mine to level with the new shocks but it appears the issue may be that I'm not waiting long enough. I will try that tomorrow.

But really I came here to say that I DIDN'T KNOW I COULD GET $50 EACH FOR MY BLOWN OUT AIR SHOCKS AND I THREW THEM OUT!!!! :E::E::E::special::badidea::cry::cry::cry::cry::cry:😭😭😭😭😭😭😭
 
On my 2004 EXT, within 30 seconds or so after a cold engine start, the air pump will start up as a system "self test".

My understanding is the air pump will run for several seconds then release any extra air.

This is done as a system test and you probably will not hear the air being released.

I've only heard this test being run after a cold engine start.

If it fails this self test, you will get an error message on the dash.

To test the system under normal circumstances, drop the tail gate and then go start the engine.

Go sit on the tail gate with the engine running and wait.

After 20-30 seconds, the air pump should kick on and pump the shocks up to raise the rear end.

It doesn't take a ton of weight on the dropped tail gate to drop the rear end enough to kick on the air pump.

If you think you need more weight, just toss some stuff on the tail gate before you have a seat.

I'm plenty heavy by myself to get the job done.

The delay is built in to prevent the air pump from cycling off and on constantly as the truck just drives down the road.
 
On my 2004 EXT, within 30 seconds or so after a cold engine start, the air pump will start up as a system "self test".

My understanding is the air pump will run for several seconds then release any extra air.

This is done as a system test and you probably will not hear the air being released.

I've only heard this test being run after a cold engine start.

If it fails this self test, you will get an error message on the dash.

To test the system under normal circumstances, drop the tail gate and then go start the engine.

Go sit on the tail gate with the engine running and wait.

After 20-30 seconds, the air pump should kick on and pump the shocks up to raise the rear end.

It doesn't take a ton of weight on the dropped tail gate to drop the rear end enough to kick on the air pump.

If you think you need more weight, just toss some stuff on the tail gate before you have a seat.

I'm plenty heavy by myself to get the job done.

The delay is built in to prevent the air pump from cycling off and on constantly as the truck just drives down the road.

Thanks EXT.

I would say my experience so far is similar to yours. Generally the air pump does not run under normal circumstances. Maybe one out of every 5 starts, or maybe just cold starts. I usually do not hear it, although I'm usually not listening for it either.

However, when I was adding or subtracting the trailer weight, the pump would turn on for about 1 second approximately 5-7 seconds after starting the truck. No codes. When I would attach the trailer, pull the main air line, and let the shocks drain almost completely, then reconnect the line, I could get it to kick on for enough time to pump the truck back up to height. Then when I removed the trailer weight, it did not seem to return to the normal height. This also was not consistent - it worked the first time, but the 2nd time I had to turn the car on and off 3 times before it leveled it back to height.

However, I don't think in any of my tests I was waiting 20-30 seconds (when you're just waiting for something to happen, 30 seconds is actually a pretty long time). That includes inflating or deflating.

Question: Does the truck have to be on for the deflation/inflation to happen? I assume that it does.

Also, I say "no codes" but a couple of times it did give me the "Service Ride Control" error message after trying the pump for 1 second. I hit the Enter (arrow) button on the steering wheel and it would go away. Then it would not come back after cycling the truck on and off again. I haven't seen the error code after several times of trying different things.

I did pull the battery for 10 minutes to reset the suspension control computer (I read in some places that this was necessary?). The SRC message has not returned since then.

But, later today on a lunch break or something I will go hook up the trailer and run a stop watch to see if it cuts on after a longer waiting period. I'm hoping this is really the "issue."

A couple of notes for posterity as well: 1) the air pump itself obviously works, and it is a Suncore replacement. I don't know if the exhaust valve is working properly or not. 2) the air shocks I bought are not Arnott, they are some other Amazon brand. They do have the resistors built into them to fool the RTD.
 
I am not certain if the key must just be on or if the engine must be running as I have only run my tests as I described above.

I am certain that nothing will happen if the key is off.

My old leaking air shocks would bleed totally down overnight and the dead truck did not attempt to air them up with the key off.

When I started the truck up in the morning for the day, the air pump would completely fill the shocks and the bladders would remain rock hard until the truck was put away at the end of the day.

When I go to the storage shed to attach my party barge to head to the lake, I will open the shed doors and back my truck up to the trailer.

I leave the truck running because there is usually a family member or two still sitting inside the truck cab and I want to leave the a/c running while I am working to get the trailer hooked up and the rig pulled out onto the parking area.

As I lower the trailer hitch down onto the receiver ball, the weight of the trailer tongue begins to drop the rear end of the truck.

Within 20-30 seconds, the air pump kicks on and the rear of the truck comes back up to it's normal level.

I can clearly hear and see this action as I am working at the back of the truck at the trailer hitch.

One thing we have not mentioned is the functionality of the ride height sensors.

You will find one at all four corners of the truck located between the truck's frame and the suspension.

Perhaps a capable scanner can read the condition of all of the associated components.

Maybe a trip to the dealer for a diag with their scanner is called for in this situation.
 
Thanks EXT. Yeah, scanner is definitely something to consider if the longer wait doesn't pan out. I will probably go ahead and spring for one given that I expect to have this truck for the next 10 years or more. Being able to perform thorough diagnostics will probably save me trouble in the long run. I'm going to do some searching on good Tech-II scanners.
 
But really I came here to say that I DIDN'T KNOW I COULD GET $50 EACH FOR MY BLOWN OUT AIR SHOCKS AND I THREW THEM OUT!!!! :E::E::E::special::badidea::cry::cry::cry::cry::cry:😭😭😭😭😭😭😭
How do you get $50 each for the old ones? I'm going to replace mine after this kitchen project is wrapped up..
 
OK, hooked up the trailer with the truck running and within 20 seconds it went up to the correct height. However, I believe I had deflated the airbags last night so that would be somewhat consistent with it's behavior before. When I took the trailer load OFF, it did NOT deflate. I even ran it down the road real quick (2-3 minutes) to give it some time and it still never went down. Cycled the trailer load on and off again and no change.

To be fair, I've only ever had the system deflate once and that was after some time overnight I believe.

So for some reason it's either not getting the right height input every time OR it's just not making the right decision when it gets it. Not sure. As far as I can tell the system still *thinks* it's working correctly, as I have no DIC message (but I know that's not a guarantee).

I'm planning to take the camper this weekend just for a night. Given that I can usually coax it into inflating - more important than deflating for now - I'm going to go ahead with it as is for now. I've ordered the BlueDriver OBD reader because it's affordable, better than what I have now, and I'm optimistic I can get some kind of clue from the computer what is going on. Even the knowledge that the system really thinks everything is fine could ultimately be helpful. We shall see this weekend.
 
The Bluedriver will most likely not read deep enough to give you any insight into what's going on with the suspension system.

I have a Bluedriver and I like it as it does a good job for most common issues you may have.

Not a waste of money, but most likely not capable enough to get the information you are seeking and certainly is not good enough to control many functions concerning deeper systems.

A dealer scanner or a good Tech-II clone is what you will need.

The dealer's Tech-II is able to command most systems to turn off and on.

Now, let me share a situation I came across several months ago on a Facebook group for Escalades, Yukons and such.

The post I read was from a Yukon Denali XL owner that was complaining about his truck having an extremely harsh ride.

He had started out with blown out air shocks and burned up air compressor and he had replaced all of that.

As soon as the new parts were installed, the air shocks pumped up as expected, but the rear end ride was much harsher than he expected and he was ready to ditch the air leveling system all together since he determined the functioning air shock system was junk.

The ride had gotten so bad that he even disconnected the air lines and let the shocks go flat.

To make a too long story a little shorter, after he tried several things suggested by many people to no avail, he finally took the truck into a dealer service department and they were able to determine the problem was a faulty suspension module that was making the air pump run all the time and thus made the air shocks overinflate and become rock hard.

The dude had no working rear suspension to speak of.

No wonder the truck rode like a log wagon.

They installed a new module and the entire system began functioning normally.

In his case, finally getting the right people with the right tools solved a problem that none of us could for him.

And to think he was right about to ditch the air leveling system over something none of us had ever heard of before.
 
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Drives me nuts to pay someone to diagnose something with just a computer, and I have just had bad luck with dealer competency around here. But we'll see. I'm hoping I can find a way to make the blue driver tell me something but if not I'll see about the dealership.

Unrelated, is there a way to make the fog lights stay on? I have to push the button every time the truck starts if I want them on. Seems weird.
 
There have been mentions on this forum concerning good Tech II scanner clones for you to purchase.

I am surprised someone has not mentioned them, yet.

I don't have one, but perhaps a search of the forum might give you some good information.
 
Yesterday I picked up some fencing supplies and when I put them in the truck the Service Ride Control message came on. So maybe it will throw a code that the BlueDriver can read. It seems like it can read C codes, which the suspension should be. We'll see, I bought in on Amazon in case I decide it doesn't work well enough I can return it.

Hard to find info on the Tech 2 clones, other than just on ebay and from china. I'd like to have more confidence in what I'm getting but we'll see. BD arrives Saturday so we'll see where that gets us.
 
Received BlueDriver today. Satisfied with its ability to read all of the codes.

Screenshot_20211001-143634.png

No real surprises here. I'm sure the C0590 code is because I left the RTD bypass resister unplugged. The exhaust code is also not surprising because I have never seen the truck lower itself. I wonder if that's also why it's not fully inflating - maybe it goes through it's initial check, realizes the exhaust valve isn't working, and then shuts off. The pump doesn't run for 4 seconds as many have said around the forums, it only runs for like 1 second, so that would further support that idea.

Note that none of these appear to be CURRENT codes, they are "HISTORY" but I don't know if that's normal or not. I haven't cleared anything yet, so I will do that and see.

I probably should have started a new thread for this issue and I may do that later.
 
The exhaust valve is part of the air pump.

I wonder if it is rebuildable.

I have seen dryer rebuilt kits, but I have not see an exhaust rebuild kit.

When I Googled, I did see mention of a check valve rebuild kit for a different GM vehicle, so I wonder if there might be something out there you could use.
 
I am going to pull off the pump this evening and see if I can figure it out. I read somewhere deep in the Internet that there was someone who was able to remove the solenoid and clean it. I suspect though that it's only a temporary fix. I do want to verify though that the solenoid is bad and it's not a wiring issue somewhere else. I have ordered an Arnott pump from Walmart that I can return if the pump turns out to be good (it is a Suncore replacement, but who knows how old), but I'm pretty sure it just needs to be replaced.
 
You enjoying this saga yet? lol

I pulled the pump and disassembled what I'm pretty sure is the exhaust solenoid. It's an interesting contraption and I can see to some degree why it's not serviceable given that it's integrated into the wiring harness with no separate clip. Still, something that could have been easily remedied. Anywho, there was signs of dirt rust and corrosion in there. I cleaned it out best I could but I think probably the motor itself under the pink "electrical tape" was probably corroded as well. I didn't look too closely but I'll probably disassemble it when I take it out and put in the new pump.

I considered verifying that there wasn't an electrical issue elsewhere, but honestly swapping the pump will take 5 minutes, which is less time than his amateur electrician would spend trying to decipher wiring diagrams. So i'm going to just put the new pump in and if that doesn't fix the issue then I'll start hunting down wiring. A quick once over of the wiring along the back frame didn't reveal anything obvious, everything looks to be in good shape. So I expect the new pump, arriving Wednesday, will solve the issue.

There is a very slow leak somewhere in the system as once pumped up it does leak down overnight. So that will be the next thing to check, but it's very slow right now so I don't consider it critical.
 
Closing the loop on this issue and probably this thread. Replaced the air compressor, cleared all the codes, and everything seems flawless. I didn't realize how bad my air compressor was because it didn't seem that noisy, but this one is silent, I had to get right next to it to realize it was working. I'll hook it up to the trailer to make 100% sure everything is copacetic, but I think we can call this one done.
 
Outstanding!

:) (y)
 
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