2020 limited air suspension issues

[njxrayman]

Has anybody had a “go flat” air suspension problem? I have a 2020 limited currently with 215k miles, suspension worked flawlessly till 185k. Just goes crazy and drops to the bump stops- sometimes just the rear…sometimes all 4 corners and I’m driving a kids low rider! It pumps back up- but can take a mile or so far, as much as more than 150 miles. I travel all the time as the mileage suggests and I can’t just run to the dealer when it happens. The truck is not overloaded and completely stock. My dealership has been great for a small dealership, they have changed the sensors, compressor with module (twice), inspected the lines and recharged it multiple times. When it acts up, the control switches “try” for a while, then become completely unresponsive. The compressor will run till it apparently overheats and does a blowoff noise. I’ve videoed the many messages of “desired height not available”-“service system immediately”- “system cooling down”- “ride height not permitted “-“Payload exceeded “… you name it, I’ve seen it! I’ve got maxcare- unlimited mileage-so expense is low (dealer hasn’t even charged me the $100 deductible yet cause it just doesn’t seem to get fixed), but frustration is very high. Anybody ever gotten this sorted out before? I’m thinking wiring connections may be poor but dealer say seem ok. I don’t know what “seems ok” means… I don’t see anybody really talking about this, so either I got the only one… or did everyone just give up?

 

[Reverse]

Have they checked the 'brains'? Is that what you meant by 'module'? That or a bad ground maybe?

Sidenote: I thought I was high on miles on my 2020 Limited (156,000), but you are the champ, sir!

Hope you get it fixed soon.

 

[njxrayman]

Have they checked the 'brains'? Is that what you meant by 'module'? That or a bad ground maybe?

Sidenote: I thought I was high on miles on my 2020 Limited (156,000), but you are the champ, sir!

Hope you get it fixed soon.

Thanks, they tell me the brain is a part of the compressor assembly on this model and comes with it. That makes 2 they have tried so far. I agree with your suggestion about a bad ground. It’s so intermittent. Works for a month sometimes- then crappy for a week or two…. Just inconsistent! Appreciate the feedback!

 

[kapinallinen2]

Thanks, they tell me the brain is a part of the compressor assembly on this model and comes with it. That makes 2 they have tried so far. I agree with your suggestion about a bad ground. It’s so intermittent. Works for a month sometimes- then crappy for a week or two…. Just inconsistent! Appreciate the feedback!

I second on a possible "poor" not necessarily a bad ground. Check the one next to the driver side hood hinge, it needs to be spotless, fixed my wonky air suspension and parasitic
battery draw problems.

 

[njxrayman]

Thanks for the tip! That would be awesome if it turns out to do the trick! I was trying to figure out how to get the dealer to check the wiring harness pin to pin for corrosion or breaks. Was yours found through diagnostics- or did you discover it yourself?

 

[kapinallinen2]

Thanks for the tip! That would be awesome if it turns out to do the trick! I was trying to figure out how to get the dealer to check the wiring harness pin to pin for corrosion or breaks. Was yours found through diagnostics- or did you discover it yourself?

Diagnosed my self with a multi meter. Had a 0.1 volt differential from the -battery terminal to the actual stud, cleaned off a thin layer of hazy oxidization and the problem went away.

 

[njxrayman]

Just check my connections- unfortunately, my voltage is exactly the same at the post and the stud. Checked the other ground studs around the engine compartment- all exactly the same. My dealership just told me they found a TSB about rear upper and lower control arms may have binding bushings that can prevent movement till the pressure gets very high…. They are firing the parts cannon again… I don’t know how I can be bouncing off the bump stops and not have movement in the bushings.. but - I’m not the engineer here.

 

[kapinallinen2]

Just check my connections- unfortunately, my voltage is exactly the same at the post and the stud. Checked the other ground studs around the engine compartment- all exactly the same. My dealership just told me they found a TSB about rear upper and lower control arms may have binding bushings that can prevent movement till the pressure gets very high…. They are firing the parts cannon again… I don’t know how I can be bouncing off the bump stops and not have movement in the bushings.. but - I’m not the engineer here.

Just to clarify, positive probe at the - battery post, not the clamp and negative at the actual threads of the stud that I had removed the paint from.
Also to add, my air-suspension troubles were a secondary issue stemming from a parasitic draw that was draining the battery causing the modules go haywire. So most likely not related to your situation.

 

[njxrayman]

Let’s just verify ( I may be an idiot). I’m putting my positive lead on the positive post, and moving my negative lead from neg post (reads 12.48v)- then I take my neg lead to the ground post and it reads 12.48v also. Am I doing it right?

 

[Scap]

Let’s just verify ( I may be an idiot). I’m putting my positive lead on the positive post, and moving my negative lead from neg post (reads 12.48v)- then I take my neg lead to the ground post and it reads 12.48v also. Am I doing it right?

I think he's saying put one lead directly on the negative post of the battery and the other lead on the ground you're wanting to check.
If you have any potential difference shown on the display that could be your issue. Ideally there wouldn't be a voltage read between these two locations.

 

[kapinallinen2]

I think he's saying put one lead directly on the negative post of the battery and the other lead on the ground you're wanting to check.
If you have any potential difference shown on the display that could be your issue. Ideally there wouldn't be a voltage read between these two locations.

This.

 

[njxrayman]

Thank you, I think you’re right- I’m going to recheck the correct way as soon as I can.