Another Air Ride thread

[Bronco_Bustin]

I've searched online and this forum and have found many people having issues with their air ride

But my 2000 Continental seems to be a little more specific of a problem

The airbags would deflate completely and bottom out over night. They would refill once I turned the ignition on and stay refilled.
I jacked it up and sprayed soapy water on everything and couldn't find any leaks.

So I then thought it might be temperature related... until one day I cleaning the back seat and heard a loud click.
And the air bags immediately deflated. It sounded like a relay/solenoid clicking and I could hear the air leaking,
sounded like it was coming from above and in front of the airbags but couldn't pinpoint the source.

So, since the bags inflate and stay inflated during normal use, I just let it be and have been driving it for months
letting the bags fully inflate from empty before I start driving.

Now, the passenger rear airbag is over inflated. Stuck in a really high position. So much that it drooped out the suspension
and changes the chamber. Has been for a few weeks now. So bad I can't ignore it anymore

Does anybody have an idea what is going on here? Where should I start? I thought about checking o-rings but it's the loud
random click before deflating that is throwing me off. Something is telling the car to deflate, and now over-inflate

Your help is appreciated

 

[Town]

The 2000 Continental has rear air leveling suspension with height sensors on all 4 corners. The VDM (Vehicle Dynamic Module) controls the air suspension and the shock setting individually for each wheel. So the VDM can raise or lower each rear air spring individually to maintain the correct ride height for the car. The VDM will start the compressor and open the appropriate rear spring solenoid to raise one or both rear ride heights. The VDM will open the compressor vent solenoid and then open one or both rear air spring solenoids to set the rear ride height. The Attached document shows the parts and their locations.

Above each rear air spring is a solenoid valve (that is normally closed). The solenoid connects the air spring through a pressure line to the other air spring solenoid and the compressor drier. The O rings at the solenoid seal the solenoid to the air spring mounting point to prevent air loss from the spring to atmosphere. If the spring solenoid is opened (your click sound) then the air line will be pressured to the same pressure as the spring and there will be no air loss from the spring, the vent solenoid at the compressor must also be opened to vent air from the spring, or there is a leak in the high pressure line.

The current problem sounds like a rear suspension height sensor has failed. The sensor should be vertical, but that long tube type sensor is prone to bend and collapse as a V shape if the suspension fully deflates. When that happens the air suspension control module is given a signal that the suspension trim is low and the module starts the compressor and then opens the air spring solenoid for the appropriate spring and inflates until the height sensor provides the trim level reading, that never comes.

Attached is the procedure to replace a suspension height sensor and a ride height adjustment procedure with measurements for correct ride height. To vent the rear air springs raise the rear of the car off the ground with the suspension switch on, and you should hear the air venting from the compressor vent solenoid. Check the spring has actually lost all air pressure before proceeding with spring solenoid removal.

For the earlier problem of the suspension venting completely, is to turn off the suspension switch in the trunk to immobilize the system and see if it still vents completely so you have a physical leak from springs or solenoid O rings. If the springs stay at ride height then the problem may be in the VDM opening both the vent solenoid and the spring solenoid of both rear springs. If the vent solenoid at the compressor was stuck open then the compressor would not be able to raise the rear springs to trim height. The vent solenoid can only be replaced by replacing the Compressor, so I have included that replacement procedure too, just in case I missed something.

The compressor and rear air spring solenoids can be activated by a ground signal or by a power signal. I will check the Continental wiring diagrams as to which is used (LLincoln uses both methods). An accidental grounding of all 3 solenoids may be possible.

Good luck.

 

[Bronco_Bustin]

Wow, thanks for your help Town. I'm gonna start tracking down those parts then. I'll let you know how it goes

 

[Town]

As promised, attached are the electrical diagrams for the VAPS air suspension system. It appears the solenoids are power switched by the VDM module. So that probably indicates the VDM is controlling the air spring deflation to collapse the suspension, perhaps due to the faulty height sensor.

Also attached is the suspension operation description that will explain the operation of each component.

Good luck.

______________________________

 

[Bronco_Bustin]

You had mentioned that there should be height sensors at all 4 corners... I could only find one, the driver side rear, based on the image of the height sensor on the 3rd pdf you posted. Is this right? I checked if the passenger side might have broken off but I saw no signs of where it would have been mounted (wear marks, plastic pieces, dangling wire/harnesses, etc..)

And to re-calibrate the ride height: "Configure scan tool for correct model year vehicle, Vehicle Dynamic Module.
Select Function Test selection on scan tool menu." Am I doing this at the OBDII port with a regular scanner or is their a special one for the vdm

 

[Town]

You had mentioned that there should be height sensors at all 4 corners... I could only find one, the driver side rear, based on the image of the height sensor on the 3rd pdf you posted. Is this right? I checked if the passenger side might have broken off but I saw no signs of where it would have been mounted (wear marks, plastic pieces, dangling wire/harnesses, etc..)

And to re-calibrate the ride height: "Configure scan tool for correct model year vehicle, Vehicle Dynamic Module.
Select Function Test selection on scan tool menu." Am I doing this at the OBDII port with a regular scanner or is their a special one for the vdm

The component view document PDF #1 shows the location of the height sensors at each wheel. In the electrical diagrams (second set of pdf, doc #2) Cell 40 VAPS you will see on page 40-3 the 4 sensors connected to the VDM module. I am surprised that you cannot find these 4 height sensors on your car. The operation of the dynamic suspension depends upon the 4 sensors as follows: "When it is determined that a corner of the vehicle is high, the vent solenoid opens to provide an escape route for the pressurized air. The vehicle will not lower unless the air spring solenoid is also opened to allow air to leave the springs."

In the ride height procedure, I realize you don't have a scanner capable of interfacing with the VDM, etc, but there is a manual adjustment (step 8) on the ball joints to achieve the defined ride height from wheel position to inside fender lip. Step 8 says:
"8. Note: If the proper wheel lip openings are not attainable by running this procedure, the air suspension height sensor ball studs will require adjustment to attain the desired wheel lip opening. Rerun Ride Height Adjustments procedure if the ball stud adjustment was made." Typically this is by trial and error until the correct height (as shown in procedure diagram) is achieved.

Hope this helps.

Good luck.

 

[Bronco_Bustin]

It says I may not post attachments, maybe because I'm still a new member

But I put the continental up on ramps and crawled underneath and scrutinized while looking for any other height sensor. I even took pictures that I wanted to post up as proof. The driver side height sensor is clear but I do not have a height sensor on the passenger side rear. I had other people look too because it's not hard to identify.

I don't know what to do. I imagine maybe when my mom got tires put on somehow they damaged it and removed their evidence... but I cannot find any wires or harness where it would plug into, would the tire shop cut the wires and tuck it back in to the plastic loom to hide liability?

There are 2 holes in the A-arm and a hole in the body up above where the height sensor looks like it would mount just like the other side...

Is it possible my 2000 didn't have sensors on both sides and only had 1 in the rear? Could the rear bags balanced between each other without it?

 

[Town]

It sounds like the passenger side height sensor has been removed or fallen off since your problem is fairly recent. I doubt a tire dealer would be involved in its damage or removal. Since you can see the mounting points all you need is the wiring harness that may be tucked up somewhere. Then you can install a new height sensor. Without a height sensor and the wiring to the suspension module control over the inflation of the air spring is compromised.

Since your car has independent rear suspension it needs 2 height sensors on the rear. The cars with a solid rear axle like the Town Car can manage with one sensor.

It would be a good idea to check a similar car at a wrecker, or ask someone on this forum with a Continental to show you (words or pictures) where the height sensor wiring connector is located in the harness for passenger rear.

Any kind takers?

______________________________

 

[Bronco_Bustin]

I agree, I'll try to check out another Lincoln and try to track down that connector location. Thanks again

 

[Bronco_Bustin]

I see other 98 and up continentals on here, but a lot of you have disabled pm's... would anybody be willing to take a picture of their passenger rear suspension? Particularly where the height sensor wiring harness goes?

There aren't many conti's on the road around here and I can't find anything online. Any help is greatly appreciated

 

[Town]

It seems there is not much help for you.

I checked the wiring diagrams for your car for the wiring connector location information and attached are the pertinent locations. The connector on the left rear height sensor is C413 and is shown in the first attachment, and you have found that. The harness then proceeds to the right rear height sensor at connector C406 shown in attachment 2. The harness proceeds from connector C406 into the trunk (and that should be quite visible) to connector C458 which is shown in attachment 3. The harness then proceeds to the VDM (Vehicle Dynamic Module) also located in the trunk as shown by attachment 4.

The wiring colours are Red with a black tracer for the power from the VDM to both left and right height sensors and Black with a pink tracer for the sensor return from the left and right height sensors to the VDM. In post #4 above is the wiring diagram that relates these circuits if you need additional info. I think the common sensor wire is because the sensor signals are individually identifiable to the VDM. I hope this helps you find the missing connector for the right rear sensor.

Good luck.

 

[Bronco_Bustin]

Is it possible to simply put a manual fill on the airbags? To heck with all this complexity and just fill it to ride height and check it once a month?

______________________________

 

[Bronco_Bustin]

Sorry for the delay,

But to wrap up this old thread I bought a pair of new rear air bags and the problem persisted for 3 days. Then the next morning the car was level and has been level ever since.

I can't explain it, but at least that was my solution.

Thanks Town for your help!

 

[Da_Wimp2]

Why can't I access the files?

 

[LincolnOnly]

Is it possible to simply put a manual fill on the airbags? To heck with all this complexity and just fill it to ride height and check it once a month?

Yeah 12v to compressor