I know this has been discussed in topics before. But here is what happens in my 99VT.

A few days ago I noticed that my seat suddenly felt like filled with stones driving on pretty smooth roads. I saw that the suspension errorlight was flashing, and I had this problem last year also sometimes, especially when driving over bumpy roads. Last year in september, I cleaned some connectors under the dash, and also the 6 gold-plated connectors that connect to the 6 shocks. Since then, the problem did not return anymore, but it can also be a coincidence.

Why I don't think it is one of the shocks leaking, is the fact that when using the diagnose procedure, BOTH front shocks show faulty according to the procedure. I can hardly believe that this would happen to both sides at the same time. That is why I would like to know: does somebody know where the shocks are electrically connected to some computer behind or under the dash ? I have the feeling that it could be a faulty contact at the connector inside the car, not outside the cabin. I have no circuit diagram of my 99VT.

And I also saw last year that the connectors I have seen were all tin-plated, not silver or gold (except the 3-pin connectors at the shocks itself). Is this true or am I mistaken ? Because that worries me for the long-term reliability.

Koni module is located under centre console, right bellow suspension switch, but it has only one connector ( about 30 pins), just like engine ecu, i dont think you have a loose connection, maybe a corroded pin?

Hey VT....

You can run the shock diag test yourself... Start with your VT turned off. There is a switch in a box under the passenger side front panel. You should be able to pull it down and out, turn the ignition switch to on (Koni ride control LED's will go off). Press the "AUTO" on the KONI switch once, the "error" LED will continuously flash (this verified that your computer is working fine and in giag mode)
Press the "AUTO" key again. If the "error" Led goes out then all is good.
If the LED has a repeatable series of rapid flashing, count them, this will tell you where the fault is:
1 flash/sec = Front left wheel shock absorber
2 flash/sec = Front right wheel shock absorber
3 flash/sec = Rear left wheel shock absorber
4 flash/sec = Rear right wheel shock absorber
If the error code are for the front wheels it is a bit simpler than for error codes for the rear wheels.
For the rear wheels because there are two shocks per wheel it will be unclear which of the two shocks are at fault. Possibility both shocks could have issues.
If there are no problems with all the shocks the error light will come back on and flash rapidly.

If you get a faulty shock in the above test. Check if the problem is related to actual shocks or is due to some other part of the
suspension control system. Start the test by first pressing the "Auto" button. Again the error light will flash. Disconnect the electrical connection
going to the shock absorber. It is a 3 pin socket. use a voltmeter. Press the "Auto" button one more time. Measure the voltage between pin 2 and 3 of the
connection from the car to the shock absorber. It should be between 0.7 to 1.3 volts. The voltage between pin 1 and 3 should be between 10 to 15 volts.
If these values are correct the system itself is OK and the failure is in the shock absorber(s) itself. Sometimes the shock is OK, its the electrical connection
in the connector that is bad. You can spray a TV tuner lubricant which will fix the problem!


Next make sure the speed sensor to the ride control system is working correctly. Again press the "Auto" button. The error light will flash again. Press the
auto button again. At this point the error light will stay on. Drive the car at increasing speed. The light should start flashing at about 20 MPH.
If it stays permanently on, there may be a connection problem with the speed indicator in the car. This will lock the suspension into a (stiff) 3 setting mode.
After all tests are completed remember to reset the computer switch under the passenger side dashboard. Switch off the ignition switch, this will reset the computer
controlled shock absorber to its normal functional mode.


Hope this helps
CCIE

Hello CCIE thanks for posting. You haven't read however my thread well as I already used this procedure .. but thanks anyway. I just cannot imagine both shocks are leaking at once or are having a problem at the same time. Also the fact that last year driving over bumpy roads produce an error light was an indicator of only bad contacts instead of faulty shocks.

In the meantime I want to say that I enjoy and appreciate the Diablo more and more everytime driving it ! I was somehow disappointed in the beginning when I was used to my SL55 that I still have. But it simple needs time getting used to the Diablo. In fact my SL55 is only sitting now in the garage. I forgive the D all its minor problems, it is a SUPER car to drive !! It is EPIC

VT did you check the voltages on the wire and the speed sensor test?
Good luck and please keep posting to what you found.

CCIE

My right shock had a bad motor and leaking seals. To check that I didn't have a broken wire I made a jumper wire / extension and connected the right side shock to the left side and visa versa. The koni diagnostic showed the error move to the left side. I also did the voltage test mentioned above, and it was correct. I then disassemble the shock and could see the motor not turn when connected, working the motor back and forth did not free up the problem. So I was then convience I needed a shock. I had John Custer rebuild the shock with a shaft and motor he had as well as he fixed the leak with his custom made seals (also got expert advice). This fixed the error light and leak. Its since been 7 months and all is well.

Thank you for your writing. Always nice to read experiences from others.

Now I have a real strange problem going on. And I must say, I have not yet measured those voltages !! (shame on me CCIE :-) I had no time last week to do that and also the next days I have no time for that. But here is what I do know :

Since the problem suddenly occured, probably driving over a bump, and having this problem a few times before last year, I thus run the diagnose procedure except measuring the voltages. BOTH shocks appear as faulty in the test, which is strange, isn't it ? Who wins the Jackpot 2x on the same day ?

This is why I did not deassemble the wheels to check the shocks, I have disassembled the dashboard to have a look at the KONI controller. What suprised me ? the connector was not completely 'clicked in' the module ! It needed only 1 mm extra pulling out to diagnose all 4 shocks as faulty !

I also did the speedsensor test and it passed, although it does not need 20mph to show that, already at some 5-10mph it shows to be ok.

BEFORE I clicked in the connector, the suspension system was always adjusted at stifness 3 which always happens if the system gives an error light.

AFTER clicking in the connector, the error light is still there, (it still shows both front shocks are faulty) but the system seems to work ok. I can manually adjust all 4 positions, and if on automatic, it automatically adjusts as function of speed ! So no permanent stifness 3.

Also when the car is stopped (and the position was stiffness 1), and then turning on the contact again, the light stiffness 3 is lighting ... Then putting it manually on pos. 1, and then pressing automatic mode, it works again, but the error light goes on when driving > 5-10mph ...

How can this be ?! Will the error maybe disappear as before ? Is the red error maybe generated by the LIE computer ? Or is the red light only output by the KONI module ?

I also tried to feel if the stifness settings actually control the shocks .. and it seems to work. Putting on 4 on a bad road feels rougher than when putting on 1.

I have the time to measure the voltages next week. Somebody a clue ?

ps. If anybody has an electric circuit diiagram of a 99, or other diagrams as well, would be very welcome.

Koni system has nothing to do with LIE or GFA or anything else.

-mick

Interesting thread and great info.
Do you have Custer's email and contact info?
Does he have a website?

The shock is still working great. John Custer's email is jcuster2@woh.rr.com