Hello, i recently purchased a 2004 Navigator that was in great condition and everything has been running / operating great for the last two months.

So here is my problem, the passenger side suspension is literally almost on sitting on the tire, maybe an inch gap. The other three corners look like they are at their normal height. The truck was fine when we arrived at the location but when i came out maybe two hours later this is how i found it. So somehow the air came completely out of the passenger front while turned off. When i turn the truck on and put it in gear the compressor does come on and run for a maybe 5 - 10 seconds, i would assume adjusting the other 3 corners.

Here is what i know so far:

- no check suspension light or warning on the display
- compressor appears to run fine
- i have turned off the suspension cutoff switch from the rear and turned it back on
- Here in MD, it has been fairly cold but its been cold for a while and this is the first time it has happened.
- I did have to drive the truck home like this, about 20 miles and it did not pump up that corner

What could cause only one corner to be deflated all the way, if there was an air leak or bad airbag would the entire system be sagging? I am thinking maybe the solenoid but not sure, could a bad solenoid allow an airbag to completely deflate and not allow it to pump back up and not throw a code? Now that i think about it is there a dash light that would come on if there is a fault in the suspension?

I have been doing a lot of reading on this and i see a lot about cold air affecting them but not quite sure that is my issue. I also see people having similar issues have some sort of service light on but i don't so i am a little confused, its as if the truck doesn't know there is an issue. Maybe thinks it at the correct height.

Any help or advice would be great, just don't know how much money i want to put into it or just purchase the conversion kit. Hoping this is a simple fix though.

Thanks,

Chris

 

I would take a look at the passenger side height sensor, maybe it came loose. If the height sensor was working normally it would most likely run for a couple of minutes before shutting off. The height sensor go bad more than any other part of the air suspension and if its bad its either a dealership visit or air to coil conversion.

 

Hi Chris,

Your issue could be several:

Is the Passenger Front Bag rising at all?

If the Bag is not rising at all I suspect #2 below, a Stuck/bad Solenoid
or a kink/ blockage in the air line.

If the bag is not inflating at all and the solenoid are good... The Bag or the O'rings must be bad enough to have a large leak.



1.Leaks and Kinks- Check the "Tee" connection that connects the front Air Bags--- Just follow the air line from the compressor/dryer connection
Does every thing look "Connected " and No kinks in the air lines

2. Check Solenoid operation--After vehicle sits overnight -Remove the Passenger Front Tire. Put Jack Stand to support Frame --So that the Lip of the wheel well is about ride height, 33inches. Observe an squeeze air bag for any pressure

Observe where the air line connects to the Air Bag-- While you use a large screw driver as a Stethscope---to listen for operation of the Air bag solenoid ---- Have someone else start the vehicle... you should hear a CLICK when the solenoid is energized-- or as the Air compressor comes on. Do you notice any inflation or hear air escaping.

You can use a couple drops of liquid soap mixed with water---to leak test... the Passenger Air Bag and air line to the Air Bag


Good luck,

Charlie

 

If the hieght sensor came loose it would not cause the air bag to deflate while the vehicle is off.

The Vehicle normally lowers about 1 inch after the vehicle is parked and has been exited... from 33 inches to 32 inches from the ground to the wheel well top lip. The Air Susoension Module, ASM, stays active for about 8 to 10 hours after the vehicle is parked/exited. As you mentioned the vehicle was unattended for about 2 hours!! You did not get any Air Suspension Message!.. When you turn the ASM switch OFF do you get a Message on your Instrument panel "Air Suspension System OFF"? check it.

The Air Control Module will set the error Message---" Check Air Suspension" on the instrument panel...(This will also lock out the Air Suspension relay and not allow it to energize the Air Compressor/Pump)
This message is only set when these conditions occur: any of the 3 hieght sensors are out of range, the level sensor is open or shorted, or the module itself has an internal error.

You can see the Passanger side hieght sensor link( small rod about 3/8 inch in diameter and 4-5 inches long ) by cutting your steering wheel all the way to the Left.. look from the rear of the wheel well . you can use a screw driver blade tip to unlatch the clip on the bottom of the link and move it up and down to see if it moves freely a couple of inches.

Good Luck,

Charlie

 

First of thank everyone for the info, I love this forum. To answer some of the questions. When truck suspension deflated completely on the front passenger corner in the short time it was parked there was no warning message. I did a system check and all systems passed including the air suspension (even though one corner was ALL the way down). When I turn off the air suspension switch in the rear of the truck, the message does come on as expected.

Now this could be coincidence but I was out side yesterday trying to figure out how to get the passenger side up and remember reading that when the truck is placed in 4x4 Low is raises the suspension an extra inch or two. I figured I would give it a try. Put the truck in neutral and flipped the switch to 4 wheel low and what do you know, all corners raises to equal heights including the passenger front. Put it back in 2 wheel drive and lowered to the normal ride height. Let it sit got a few hours and still looked good, even after driving it to the store it was good. Later last night I ran to the gas station real quick and when I came out it look like the passenger side was deflating. Went to the wheel well and I definitely heard air leaking from somewhere. I was bummed out. Seemed within minutes it was all the day again. Thought it was going to be a bumpy ride home but when I turned on the truck and started to pull out the compressor came on and pumped it back up. This morning it seems to appear normal. This is driving me crazy now. And to note, at no time have I had any warning messages or notices on the dash and the compressor has always come on.

Again thanks for all the help, hopefully with help of this forum I will figure it out.

Chris

 

When you get home with it inflated normally before shutting of the care disable the switch. Measure the height and then do it later. If it not deflating then most likely there is no leak in the air bag itself. Now when it goes to kneel it has to open the solenoid to let air out. It could be the solenoid is sticking open or the height sensor is kind of working but not completely. If you go to 4WD low and it air up another inch and the swich back to 2WD do all corners come back down to trim height. The solenoid is a cheap enough part if you are replacing it yourself to try it but if not then if it happens often enough that is acts up at the shop they can diagnose it quickly. A sensor replacement is not cheap but it less than a conversion if that is all they do.

 

UPDATE: Thought I would provide an update as to where I stand with my issue. I have not replaced any parts up to this point but kind of have a work around, more a bandaid then a fix. So my front right suspension will almost always be completely deflated if I leave it for some time, can't really determine what that time is but it will go all the way down. The odd thing is, when it is all the way down and I turn on the truck the air pump comes on and runs for a minute or so but the front passenger corner rarely pumps up. However, if I put it in 4x4 low, the pump comes on and runs for about 30 seconds and then all the sudden you will see the truck rise, all 4 corners to the 4x4 height. This happens every time too, so to get my suspension to the proper height I simple put it in 4 wheel low, let it pump up, then back to 2 wheel. It then drops all four corners to regular height until I turn it off and leave it.

Now I did not want to continue putting the truck in and out of 4x4 low just pump up the suspension. What I have done is inflated it completely up on a level surface, and then tiurned the suspension switch in the back off. My Navigator has now been at a good level ride level for the past two weeks without deflating. I only get the expected message when I turn the truck on that the suspension switch is off. I clear it with the press of two buttons and away I go. I don't miss the "kneel" feature at all so this works great for me. Would still like to solve the problem but this will get me by until the weather is a little warmer to work on it.

If anyone has any other ideas of what is wrong from my update please let me know, maybe the solenoid as mentioned.

Thanks again

 

I suppose at this point the most logical part giving the problem would be the right front height sensor. There could be a dead spot at normal height, which is why it will pump up when you go into 4Low. The ride height module looks for a higher level when in 4Low, so it naturally looks for a different spot on the height sensor. Just my theory though.

 

Their is definetily a difference in the 2WD and 4X4 Exped and Nav suspension set up.

I will have to Look at the 4X4 wiring Schematic to determine the difference in operation. I will be unavailable for a couple of weeks but will get back to you folks.

The major common element to the 4X4 and 2WD systems is the Air Suspension control module, on the Driver side under the Dash... You may want to Disconnect and inspect the pins for any corrosion etc...on the cables and the Module --- Then just plug them back in,

Regards,

 

My bet is that cracks are exposed on the fold of the rubber when at the lowered height. The cracks kind of seal themselves(for the time being) when the vehicle is higher.....and the fold is further away from the cracks.

You will probably notice it'll leak allot worse the colder it gets, as the rubber can't seal itself as well when the rubber is cold(hard=less pliable)

In my experience, I would strongly recommend doing a coil conversion. Its a ton cheaper and the only way you can rely on the vehicle again.

 

I know this is an old thread but to the OP what is the update? Did you repair it?

 

This is very old but I'll explain what's going on with my 2004 Navi. I was driving on Saturday and the Check Air Suspension message came up. The car drop from the passenger side front. I can hear the Compressor running. The odd thing it brings it to the normal height and all of sudden you can hear fast deflating on that side. The compressor would try to inflate it again, but it stays down. Any idea what could it be?

 

It's obviously an air leak, but most likely a bad air diaphragm inside the air shock.

 

Thanks for your speedy reply. Does it mean that I may need to replace that airbag?

 

Yes if that turns out to be where it's leaking.