Bentley GT suspension ride height
 

Messing around on vagcom I came across the suspension level settings and noticed every corner has a different height variation.

Assuming tire pressure is correct should one correct these values via vagcom?

Thanks!

i'd find a flat/level pad, do some physical measurements and correct as needed. Then roll the car a bit, get back on pad with your car pointing in the other direction (just to be sure) and remeasure just to verify. When we corner weighed my Ferrari and the Formula 2000 track car we also unhooked the anti-roll bars, yet don't think that is really 'needed' here. i'd trust actual PHYSICAL measurements versus what VAG says.

I would be careful with this. Tire pressure doesn't matter, because you would measure from top of wheel well to center of wheel, not ground to wheel center (see Pic). The adjustment can be finicky, when you start the process you will get an air suspension error. If the car does not get the values it wants, it will not complete the adjustment and stay in fault mode. Sometimes, the car will fight the values you give it and you have to find the range of values the car wants. While doing the test you should not sit inside the car. Also must be on a flat surface.


You will always have some play doing this adjustment too. Just try measure, then rock the car suspension by bouncing the car up and down and you see the values will change.

Oh, by the way there are also 3 preset ride height settings available, if you want different ride height. One is used for European (lowest), one higher (due to bad roads, speed bumps, etc) for US cars, and thirdly, another, I don't remember which. These settings are available using your VCDS

Thanks Steven / Zaos for the input.

Zaos, does it mean I can just program it for say EU setting and all 4 corners will adjust automatically?

Thanks

Yes, It will lower/raise prescribed setting (not calibrate). If you own an Audi, you can actually set this using the MMI (at least on mine). But with the Continental, you have to use the VCDS. Not sure exactly where it is in the VCDS. If you are having trouble I can look it up over the weekend.

However, I think you need a pass-code before you do this and it should be "31564"

Here are my notes. Some of them are blatantly copied from places on the net. I have no recollection where I found them. These are just raw notes to myself, so I remember. Please, don't flame me for plagiarism:



Address 34: Level Control
Protocol: KWP2000
Part No: 3W0 907 553
Component: LUFTFDR.-CDC- 3C1V0 7014
Coding: 0015500
Shop #: WSC 00083

[Security Access - 16]
Enter 31564
[Do It!]

Coding

The suspension controller is controller 34. The normal coding for this controller in Europe is 0015500, and the normal coding for this controller in North America is 0017700. Each increment of one digit in the location where the 5’s and 7’s are is equal to a 5 mm increase in body ride height above the axles. If you change the coding of the suspension controller from xxx77xx to xxx55xx (the x representing digits you don’t pay attention to, and should not change), then you will eliminate the 10 mm upward adjustment.

So, using your diagnostic scan tool, change the coding of the controller, save your work, and close the controller. Now, because you have changed the coding, you must re-adapt the controller – otherwise, you will see a message in the Y24 display (the screen between the speedometer and the tachometer) telling you that you have suspension problems. In fact, this message will appear immediately as soon as you change the coding – don’t worry about it, it will go away once you have completed the adaptation.

Change the coding from xxx77xx to xxx55xx – no security code is needed or wanted for this step.
Don’t forget to save the work after you do this.

Adaptation

Put the car on a level surface. Make sure that the tire pressures are correctly set on all 4 tires. Get whatever you need out of the car, because you cannot open any doors or lids during the adaptation process (if you do open a door or lid, it aborts the adaptation). Roll the driver window down all the way. Plug the cable from the diagnostic scan tool into the OBD (on board diagnostic) connector, which is just inboard of the parking brake foot pedal. Run the cable out the open driver door window, and plug it into your diagnostic scan tool (now you know why it helps to have a bar stool to put the scan tool on).

Start the engine, and leave the car idling, in Park. Get out, and close all the doors.

Open the suspension controller (address 34), and enter the security code that is needed to give you access to the adaptation section of the controller. The security code is 31564 – this is the same for a Touareg or a Phaeton. Be aware that once you have entered the security code, you have initiated the adaptation procedure. You then have to fully complete the adaptation cycle – if you back out before the end (channel 5), your car will display a fault message, and the suspension system will be in ‘limp home’ mode.

Enter the Security Code

Once you have entered the security code, go to adaptation, and select channel 1. The Bentley will then move up and down a little bit, and eventually, ask you to enter a measurement. Measure the exact distance between the axle centerline and the bottom edge of the front left fender, and enter that value. Repeat this process for adaptation channels 2, 3, and 4, which correspond to the front right, rear left, and rear right wheels.

Go to channel 1, wait for the car to move up and down, then enter the observed measurement
Normally you have to wait about 1 minute until the car stops moving up and down, rarely longer than 2 minutes.

When the word WAIT disappears, and ENTER appears, enter your measurement.
VAG-COM software will occasionally 'hang' on adaptation channel 1. If the word 'wait' has not been replaced with 'enter' after 5 minutes, just dismiss the yellow guidance balloon (click on the X in the corner of the balloon), then enter your measurement, and click test, then click save.

How to make your measurements
Keep the ruler level, use a credit card to line up with the center of the axle. It helps to mark the desired measurements (401 mm and 407 mm) on the ruler with a felt pen.

Once you have entered the measurements for all 4 wheels in channels 1 to 4, you then have to go to channel 5, and enter a one (1) to save your work. Entering the 1 tells the controller that you want it to write the values to memory. If you don’t do this, you won’t successfully complete the adaptation.

After you have entered and saved the 1 to channel five, close the controller. Then get in the car, back it up about 15 feet, then drive it forward about 15 feet, so you are back in the original position again. Leave the engine running, and without hooking up the scan tool, take the 4 measurements again. You should find that the measurements are within 5 mm of the nominal distances – that is to say, 401 front and 407 rear if you have coded the controller with 5’s, and 411 front and 417 rear if you have coded the controller with 7’s.

If the measurements are outside of that range, or, if they are inside of that range but you want to make them more accurate, repeat the adaptation process again, starting with the entry of the security code. It’s not uncommon to need to complete two adaptation cycles to get things perfect. Once you are within 2 mm of nominal, stop, because that is about as close as you can reasonably expect to get.

Experience has taught us that it is kind of pointless to try to go through more than 3 adaptation cycles in one day. If you don’t get the results you want after 3 cycles, put the car in the garage and try again the next day.

Background Information

You can increase the Bentley ride height up to 20 mm above the nominal European settings – for example, if you had to drive the Dempster highway to the Arctic ocean, this might be worth considering, you would enter 9’s as coding values – but it seems that you cannot code the controller with a number that is lower than 5. You can try, but the controller won’t accept it. My guess is that you need to have a different security code (that we don’t know about) to enter values lower than the European norm.

Some people have managed to get the car to sit quite low on the axles by ‘fibbing’ to the controller during the adaptation process. In other words, they take the measurement, and if the measurement is, for example, 401 mm, they enter 406 mm. This tells the car that it is 5 mm higher than it thinks it is, and the car responds by sitting 5 mm lower when the adaptation cycle is finished. Personally, I don’t think this is a good idea. If you lower the car the ‘proper’ way – by coding – then do a truthful adaptation, the car knows exactly where it is at all times, so far as limits of suspension travel are concerned. If you fib to the car when you do the adaptation, then it will think it still has (for example) 30 mm of downward or upward shock absorber travel before it hits the physical limit of travel, when in actual fact it has only 25mm of downward travel, and 35 mm of upward travel. This will result in less than optimum suspension performance at all times.

Great post, thx!

Interesting thread. I have a more basic problem and wonder if anyone may have some pointers: So, for a while, the car suspension has been "leaking" air on the rear. Looks like RH side rear. Symptom is the car sits very low after being parked for a while, and the compressor working more than it should.
Bentley dealer inspected and told me its one or both air suspension units being leaky, and needing changing. All agree the RH side unit was the suspect since the car "sunk lower" on the RHS, with the LH side evidently catching up.. So, bought a unit from Bentley UK. Car is in Spain at moment and Bentley here refused to change it (citing warranty etc but clearly wanted to sell their own, even more overpriced part). Used a v. experienced indy and changed the RH unit (expensive new original part). Shock horror - no change! Seems I have changed a perfectly good unit, and the leak must be somewhere else. But where?
Am going to have to get it diagnosed, but if anyone have experience of where such a leak could be it might help narrow down the suspects.. Thanks.

Zaos...the depth of your knowledge on subject is astounding....speaking for myself and I am sure others, your graciously shared information enlightens us on many subjects relating to our Bentleys....could you please respond to the Turbo Charger Dump Valve issue raised by our friend in Greece...Thanks...JimB

Tuesday Feb 14, 2017 3:45am
Hello Zaos...Can you share any information on the function of the Dump Valve on Yurbo...I see a comment that the B original "rubber diaphram" is prone to failure....is that a bit that can be serviced without engine out...thanks JimB

Hi Zaos

I thought it would be a good idea to calibrated the suspension having replaced front pair. Following your instructions I was able to successfully complete this task.

I did check my coding and find I'm using European "55" but have a question regarding digit 6 which is engine type. Vagcom pop up help menu shows option 1 for GT and 3 for FS but mines coded 6.

Do you have any idea what the 6 represents and if I should code it to correct engine type 1?

Thank you
J

THANK YOU Zaos - Bentley air suspension calibration
 

Hello sir

Thank you thank you thank you thank you thank you thank you thank you thank you

What a blessing these chat rooms are for a DIY and all who contribute.

I followed this procedure several times however when I got to channel 5 for saving to memory it would not do it. My soft code was 0005551

A pop up window explained each digit however it would not allow me to change the digits to match the code in your article. The five next to the one was not one of the choices for that location. My flying spur should have been 3 therefore soft code number 0005531 when I put that three in and went through the process again it allowed me to proceed to channel 5 and input 1 for save
Per your instructions. Magically it saved the information and the fault code on the dash disappeared and the car air suspension system is working properly.

Thank you thank you thank you THANK you what else can I say

Have a good day

VCDS help
 

I’m having a little problem when I get to the the last wheel (Rear Left) I get an invalid setting then and “Error Security access required” when I go to Channel 5.
Can anyone help me with this?



https://cimg9.ibsrv.net/gimg/www.6sp...c07a36f9b.jpeg
https://cimg0.ibsrv.net/gimg/www.6sp...bdf0fc8c3.jpeg

Bentley Level calibration
 

It will not let you go to channel 5 until you have successfully finished 123 and four. Perhaps the measurement you are putting in at channel 4 is too large. You could also look at the measurement block area to verify you are actually getting data from channel 4.

Every time you failed to reach channel 5 and Store a 1 you have to start completely over

It took me two days to figure out mine. My problem turned out to be that the soft code number was missing the proper digit for my car "flying Spur" I could not enter the soft code reference in the article on this chat room
However my version of V--- Provided a drop-down window that explained the function of each digit in the soft code once I corrected the next to the last digit (changed the 5 to 3)
Then I got channel 5 to function. And I was able enter 1for channel 5 to store my calibration results. Critical to verify you were actually getting data from channel 4
GOOD LUCK