Pressurizing air shocks……

[ReaperHWK]

I’ll tackle the c660 for the air compressor relief solenoid first. Seems like a simpler circuit and the SCM and compressor are next to each other. Easy to check for shorts and opens.

Alright back to work, one step at a time. Maybe by this time next year it will be 100% lol

 

[ReaperHWK]

Finally had time to dig into this today. I fixed all the mag ride shock codes the issue was that in one of the main harnesses a rubber gasket was deformed and preventing a few pins from making contact(that’s why the SCM had open circuit codes). Fixed that but still am working on the level control c660 code. That one is pissing me off now because I was trying to fix that one first but still can’t…….

 

[ReaperHWK]

Got it. Truck is 100% now what a ride. It was another wire that wasn’t making contact in a harness.

These trucks are wiring nightmares for sure.

 

[ReaperHWK]

@Doubeleive
One more question maybe you can answer. All the electronics work now and I have zero codes, I can pump up and depressurize the shocks with the scanner, and all the mag shocks pass their self test routines. Truck also rides good once again.

I pumped up the shocks and drove for 15 min. Came back and the shocks are flat with no air. I am assuming I may still have a leak somewhere, I’ll check later.

Do you know of the SCM will throw a code if their is a leak and it senses the air shocks are always deflated? If it does I’m thinking I’ll wait for the code to show up. I know the SCM can read the air pressure sensor and it also knows the ride height with a sensor.

 

[Doubeleive]

@Doubeleive
One more question maybe you can answer. All the electronics work now and I have zero codes, I can pump up and depressurize the shocks with the scanner, and all the mag shocks pass their self test routines. Truck also rides good once again.

I pumped up the shocks and drove for 15 min. Came back and the shocks are flat with no air. I am assuming I may still have a leak somewhere, I’ll check later.

Do you know of the SCM will throw a code if their is a leak and it senses the air shocks are always deflated? If it does I’m thinking I’ll wait for the code to show up. I know the SCM can read the air pressure sensor and it also knows the ride height with a sensor.

I don't think so it never did for me and I have not seen anyone report a code for deflated shocks
the norm is "hey my shocks are blown out and it rides like shit" what can I do? lol
people drive these around and don't even realize the shocks are literally blown out like a pair of teenage tennis shoes, how I don't know, I can tell if mine are even low psi
the codes come up when the ohm reading inside the shock is wrong or not connected or if the ride height sensor gets disconnected or fails, etc.
in some cases depending on how it fails it can limit you to 80mph as a safety feature and may not show a code

***soap and water time***
check all around the bladders and the pump and relief valve, if a airline is not fully seated that could maybe be it.

 

[ReaperHWK]

I don't think so it never did for me and I have not seen anyone report a code for deflated shocks
the norm is "hey my shocks are blown out and it rides like shit" what can I do? lol
people drive these around and don't even realize the shocks are literally blown out like a pair of teenage tennis shoes, how I don't know, I can tell if mine are even low psi
the codes come up when the ohm reading inside the shock is wrong or not connected or if the ride height sensor gets disconnected or fails, etc.
in some cases depending on how it fails it can limit you to 80mph as a safety feature and may not show a code

***soap and water time***
check all around the bladders and the pump and relief valve, if a airline is not fully seated that could maybe be it.

So the wife started the car up and took it for a drive. She pulled out into the street and I felt the shocks they were pumped up again. She drove around for 20 min and parked. Turned truck off. I went to the truck 5 min later and they were flat.

If they are pumping up and holding pressure the entire time the car is on is that the way they operate?

I’m confused as wether the shocks should be holding air after it’s turned off.

 

[Doubeleive]

So the wife started the car up and took it for a drive. She pulled out into the street and I felt the shocks they were pumped up again. She drove around for 20 min and parked. Turned truck off. I went to the truck 5 min later and they were flat.

If they are pumping up and holding pressure the entire time the car is on is that the way they operate?

I’m confused as wether the shocks should be holding air after it’s turned off.

they should hold air for a long time weeks or even longer, if it was just sitting parked

 

[ReaperHWK]

they should hold air for a long time weeks or even longer, if it was just sitting parked

Yeah you must be right. I turned the truck on and saw the shocks pump up. I was literally standing there and within 2 min they deflated. I have a good size leak somewhere. Time to get the soapy water!

 

[Big Mama]

Wes, I’m asking for myself. if there was a leak wouldn’t the compressor keep running enough for you to hear it constantly on?

 

[Doubeleive]

Wes, I’m asking for myself. if there was a leak wouldn’t the compressor keep running enough for you to hear it constantly on?

no, the pump is designed for intermittent use only
it is designed to run xx amount of seconds and shut off (per key cycle)
then (during the same key cycle) as far as i know or have experienced it only comes on again if the ride height sensors detect a load, say if you attached a trailer or a couple heavier people stood on the rear bumper.
then (also during the same key cycle) if the load is removed the relief valve opens and lets some pressure out
and I also "think" it is only able to detect that load while in park, otherwise it would be constantly trying to keep the vehicle "level" driving down the road
it's a set it and forget it type of thing, unless you are parked again and change the load (while parked)
and "my" theory about this is when it first pumps the shocks up it "remembers" the shock ohm load, then if you are out driving around and the air leaks out and you stop and park it doesn't try to re-pump the shocks because the "ohm" load is not greater than what it remembers so it does nothing.
I also believe this is how air ride delete (bypass) works using resistors because the ohm load never changes, so the system thinks all is well
nobody knows for sure except the designer.....

 

[ReaperHWK]

no, the pump is designed for intermittent use only
it is designed to run xx amount of seconds and shut off (per key cycle)
then (during the same key cycle) as far as i know or have experienced it only comes on again if the ride height sensors detect a load, say if you attached a trailer or a couple heavier people stood on the rear bumper.
then (also during the same key cycle) if the load is removed the relief valve opens and lets some pressure out
and I also "think" it is only able to detect that load while in park, otherwise it would be constantly trying to keep the vehicle "level" driving down the road
it's a set it and forget it type of thing, unless you are parked again and change the load (while parked)
and "my" theory about this is when it first pumps the shocks up it "remembers" the shock ohm load, then if you are out driving around and the air leaks out and you stop and park it doesn't try to re-pump the shocks because the "ohm" load is not greater than what it remembers so it does nothing.
I also believe this is how air ride delete (bypass) works using resistors because the ohm load never changes, so the system thinks all is well
nobody knows for sure except the designer.....

So I found the problem. Passenger air shock leaks like hell. Here’s a video.

The other one holds air except the rubber looks worn like the other one.

Do you suggest replacing both? Where is the cheapest place to buy the OEM shocks. Lastly, looks like an easy job and I’m assuming no programming is required at the dealer for a shock replacement?

This should be the end to my saga….. hopefully?

 

[Doubeleive]

So I found the problem. Passenger air shock leaks like hell. Here’s a video.

The other one holds air except the rubber looks worn like the other one.

Do you suggest replacing both? Where is the cheapest place to buy the OEM shocks. Lastly, looks like an easy job and I’m assuming no programming is required at the dealer for a shock replacement?

This should be the end to my saga….. hopefully?

ya that's a leak for sure
replacing them is plug-n-play, once you are all done with it, then you "could" do a ALC trim calibration but it's not required. all that would do is set the computer to see the "static" baseline of the suspension, vehicle parked level, unloaded, full tank of gas.

shocks are probably the cheapest on rockauto
the oem ones now have a lifetime warranty
arnott have a 2 year, they used to have lifetime but changed there policy, they are a quality replacement mine are around 5-6 years old and are still perfectly fine.
one thing to note is be aware that the rear abs sensor harness sits right on top of the frame directly above where the shock top bolt goes and it is not uncommon for people to accidentally knock the harness loose when changing shocks. so just keep that in mind if you do the shocks and then go drive it and get a abs error....

 

[ReaperHWK]

Thanks I’ll probably replace both of them then. My scanner does the ALC so that’s no problem.

Thanks for all your help you really helped me out a ton with this problem.

 

[Doubeleive]

Thanks I’ll probably replace both of them then. My scanner does the ALC so that’s no problem.

Thanks for all your help you really helped me out a ton with this problem.

ya I forgot to say it's probably wise to replace both as the other side will likely be the next to go in short order
same for wheel hubs and heater hose T"s

 

[Tahoe14]

There is a 5% discount code listed at the beginning of this forum under “preferred vendor sales”, every little bit helps.

 

[ReaperHWK]

ya I forgot to say it's probably wise to replace both as the other side will likely be the next to go in short order
same for wheel hubs and heater hose T"s

I replaced both today. I turned on the car the compressor pumps up and only the driver side gets blown up and the compressor turns off. The passenger side shock remains flat. I pulled the air connector off the passenger side and a gush of compressed air comes out which says that line has pressure. But the shock doesn’t inflate……

What do you think is going on here? The old shock inflated but leaked. The new one won’t inflate. I’m thinking of just getting the old one connected on the passenger side to see if it will inflate, what’s the odds I got a new shock that is defective?

 

[Doubeleive]

I replaced both today. I turned on the car the compressor pumps up and only the driver side gets blown up and the compressor turns off. The passenger side shock remains flat. I pulled the air connector off the passenger side and a gush of compressed air comes out which says that line has pressure. But the shock doesn’t inflate……

What do you think is going on here? The old shock inflated but leaked. The new one won’t inflate. I’m thinking of just getting the old one connected on the passenger side to see if it will inflate, what’s the odds I got a new shock that is defective?

that's weird, did you try seeing if there is anything in the hole where the line connects? piece of plastic blocking it or anything? plastic plug that got shoved in?

 

[ReaperHWK]

that's weird, did you try seeing if there is anything in the hole where the line connects? piece of plastic blocking it or anything? plastic plug that got shoved in?

I fixed it. Weird issue that I don’t think if I had a bidirectional scanner could be fixed.

So the passenger shock airbag was “rolled up” and the compressor couldn’t get enough pressure to “unroll” it and it wouldn’t inflate. I had to jack the rear into the air to unload the shocks and then command the compressor to fill the shocks to max psi and the passenger shock finally popped out and filled. I’m good now.

 

[ReaperHWK]

Finally all this crap works. Truck rides amazing. When the mag ride and air suspension work it’s one of the best rides you can get for sure. It’s amazing how often they adjust even when I move in the seat the suspension adjusts. Cool to see it on the scanner. You can see the shock current go up on turns on one side to stiffen the suspension to minimize body roll as well. It’s a cool system.
Can’t believe some of you guys delete it lol.

 

[Tahoe14]

Yea I don’t think they realize how nice it is. They put on new mag ride shocks and swear it’s no better which I don’t understand and then they eliminate them. Maybe they got a bad replacement, I don’t know. The scan tool as you describe would tell them if there is an issue.