2002 denali AWD how to test rear air ride??????

[WDE]

Need help what all can I do to test it or is there a link someone can post for me plzzz

 

[yates ™]

What do you mean test it? Put weight on the back and see if it airs it back up

 

[WDE]

I hauled a trailer yesterday and it would not level out. Is there any schematic layout on how to do a process of elimination of what could be causing it to no level out. Cause I have no service light on I was wondering if there is a relay or fuses you can jump to test or find leaks.

 

[yates ™]

You are going to have to be more specific. Does the compressor come on at all? Does it shut off with out the rear being level? Does it do absolutely nothing when weight is added to the rear?

 

[WDE]

Did nothing but when unloaded the truck went back to normal height.

 

[yates ™]

So the compressor is coming on but not producing enough air to fill the bags under a load. compressor is bad and needs replaced

 

[WDE]

Unless the compressor is extremely quite. Where is it located and all the relays and fuses

 

[kses123]

The compressor is behind the left rear wheel, mounted to the frame. The relay that controls the compressor is attached to the outside of the electrical center under the hood. You can jump the pins where the relay goes to test the compressor. The compressor is definitely not super quiet, you should hear it.

 

[yates ™]

You have to quit being so vague in your answers if you want help.

Like Keith said you should be able to hear the compressor. Does the system give you an error at any time? I would think if there is a blown fuse the system would still give you an error.

 

[WDE]

I have no codes I will check everything you all told me too when I get off and hopefully it will be a simple fix. But no there is no code or engine light on at all just didn't even know where to start to find the problem. But is there a way that the previous owner could have disable it maybe cause they never hauled anything on it or didn't like the noise from it. The Denali was a vacation vehicle I got from a family and that's all they used it for the husband said he never towed with it. But on he other hand it pulls great and really smooth to not have the shocks aired up. I really appreciate all the info

 

[kses123]

They most likely did not do anything to disable it. The vehicle is 11 years old, so there is a good chance that the compressor is shot. It is common for them to fail, especially if it has been exposed to harsh conditions, like salty roads.

 

[yates ™]

They most likely did not do anything to disable it. The vehicle is 11 years old, so there is a good chance that the compressor is shot. It is common for them to fail, especially if it has been exposed to harsh conditions, like salty roads.

Air leaks are the most common killer of compressors which can happen from the conditions that Keith mentioned. I am not sure of where the fuse is on this system but to my knowledge the system cannot be disabled. Does the warning come up in DIC or a warning light?

 

[WDE]

Not to change subject but my wife just called and she was driving the truck down the road and before I tell you the codes I just cleaned my k&n filter 2days ago and replaced the pcv valve here are the codesC0265
P0101
P0300
P0332 this one was on there 3 times

---------- Post added at 03:34 PM ---------- Previous post was at 03:29 PM ----------

Oh and washed the motor

 

[kses123]

None of those codes have anything to do with the electronic suspension. the 40amp large fuse (#1) in the electrical box is for the suspension compressor/trailer wiring. Check that fuse.

There is also another fuse, RTD (Real Time Dampening) #28, but if it were bad, it would have a message pop up in the DIC.

 

[WDE]

Right what could these be

---------- Post added at 03:40 PM ---------- Previous post was at 03:38 PM ----------

I have one missing and its label AIR and 40amp n both studs are present a 40and 30amp