Xantia HA2 problem

Mandrake · Post by **Mandrake** » 22 Jul 2005, 07:18

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by bernie

No DEATH wish yet.
The car is on ramps and axle stands.
The thing is you CANNOT unscrew a sphere easily whilst there is system pressure but I did because there was NO pressure behind it when there SHOULD have been.
<hr height="1" noshade id="quote"></blockquote id="quote">
Still a dangerous thing to do in my opinion, when you know that there is a computer operated valve that operates the sphere in question....valves can malfunction, so can computers...and if the car was still up, there was obviously still pressure on either side of the HA valve.
I don't take ANY chances, especially on a car that is unknown or is being worked on because it has a fault in that area...
Regards,
Simon

ActivaV6uk · Post by **ActivaV6uk** » 22 Jul 2005, 13:21

I bought some massive tipper ramps because i hate being under cars with hydraulics, however I’ve done what Bernie did and you don’t put your self in those positions with out knowing what your doing, and considering the small time I’ve spent with Bernie I believe he knows what he is doing.
So for the kiddies out there with no experience, working on cars with hydraulic suspension can be dangerous because you can be crushed very easily, so if you have to go under there put as much between the floor of the car and the road as you can other wise however little room there is when its all the way down on its bump stops, should anything go wrong that’s how thin your going to be (there is nothing wrong with having lots of structural supports under the car as long as they can all take the weight and its not off balance).
Andy

Stempy · Post by **Stempy** » 22 Jul 2005, 13:45

If you think it's too harsh a ride, why not fit spheres from a non HA model with bigger damping holes, then you'll have a plush ride in hard mode and a very plush ride in soft?

Mandrake · Post by **Mandrake** » 22 Jul 2005, 17:24

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by Stempy

If you think it's too harsh a ride, why not fit spheres from a non HA model with bigger damping holes, then you'll have a plush ride in hard mode and a very plush ride in soft?
<hr height="1" noshade id="quote"></blockquote id="quote">
No thanks,
I'm not out to redesign the car, just get it working to the standard it should be [:D] I'm fairly sure that it is not working as it should either due to low gas in the spheres or possibly intermitant solenoid operation.
I find the damping of the standard non-HA2 a bit on the soft side, so normal sphere plus hydractive sphere would be unbearably soft and squelchy [:D] I prefer a ride with firmish damping, but soft springing...and I believe that a properly working HA2 will have the balance I'm looking for...
Regards,
Simon

JohnCKL · Post by **JohnCKL** » 24 Jul 2005, 19:54

Same problem with my hydractive 96 Xantia 1.9TD. Ride is quite hard. Still trying to solve the problem. Any discovery would be greatly appreciated.

Mandrake · Post by **Mandrake** » 25 Jul 2005, 11:34

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by JohnCKL

Same problem with my hydractive 96 Xantia 1.9TD. Ride is quite hard. Still trying to solve the problem. Any discovery would be greatly appreciated.
<hr height="1" noshade id="quote"></blockquote id="quote">
Is it just the back or the front riding hard, or both ? Is it riding well sometimes and not others, or always hard ?
Do you only find it too hard around town speeds and ok at open road speeds ? (thats what I'm finding with mine...perfectly ok at 100Km)
I presume you've already checked/replaced the hydractive spheres and/or other spheres ?
Front struts lubricated and don't creak/jerk etc ?
What else have you tried ?
I will keep you posted on the results, unfortunately as its the middle of winter over here, finding a fine day off work to work on it is problematic [:D]
Regards
Simon

JohnCKL · Post by **JohnCKL** » 25 Jul 2005, 21:34

Ermmm, should have let the mech check out the spheres first. The front is hard, trying to press it down only goes 1 inch lower. Changed to used front spheres to test them out, better now, can go down about 2 inches but right (drivers) side still harder than left. Front hydractive sphere is OK. Fast speed 100kph feels OK but going over humps and holes still feel the back needs improvement. Top up with LHM after all the spills while opening and I'll see if its better tommorrow. Maybe need to oil left strut.

Mandrake · Post by **Mandrake** » 26 Jul 2005, 03:43

The way I see it there are 3 aspects of the suspension that need testing to fully diagnose a Hydractive 2 system, which is what I'll be doing:
1) Sphere pressures need checking...the best way to do this is a pressure tester, of course not everyone has one, but I have the bits to make one up again.
Because you have both corner spheres and a centre sphere its possible for one or the other to be almost flat and not easily be able to tell which, without doing proper pressure testing of each sphere.
Without the spheres being in good condition the computer and solenoids can't do their job...
2) Checking that the computer is receiving the sensor inputs and correctly making hard/soft decisions based on those inputs. The only way I can see of doing this is to somehow wire up an LED (and resistor) to the hydractive solenoid signal and putting that LED in the cabin where its easy to see while driving, so that you can evaluate the response of the computer to various stimulus.
(For example hard braking, vigourous acceleration, hard cornering etc should all trigger a switch to hard mode for a second or so)
This is easy in principle, but finding a good place to tap into the signal to the solenoids without splicing wires etc, and neatly running some wires back to inside the cabin and finding a good place to put an LED (either temporarily or permanently) is a bit more difficult than I thought.
3) Once sphere pressures are confirmed to be good, and the computer is sending the right signals, the remaining possible problem is that the solenoid doesn't actually switch when a voltage is applied to it, or (as I suspect in my case) doesn't always switch reliably.
Telling if this is the case is a bit tricky, basically you'd have to drive the car over a variety of surfaces comparing what mode the LED says the suspension is in, and how it feels. Also doing a stationary bounce test.
Regards,
Simon

xantiav6 · Post by **xantiav6** » 26 Jul 2005, 12:08

<blockquote id="quote">quote:<hr height="1" noshade id="quote"> finding a good place to tap into the signal to the solenoids without splicing wires etc, and neatly running some wires back to inside the cabin and finding a good place to put an LED (either temporarily or permanently) is a bit more difficult than I thought.<hr height="1" noshade id="quote"></blockquote id="quote">
I did this by splicing into the wires to the front valve, but doing it where the splice is covered by the plastic sleeving when finished. The wire, I just ran up over the transmission and taped a small 12V bulb to the wiper blade. No need to thread wires into the cabin.
One problem that I suspect my current car has is that this motion sensor of the front roll bar is a bit sensitive, so when gong over a big speed bump, the front goes over in soft mode, but decides the bump was too big, and switches to hard mode befor the back wheels hit it. My previous car did not do that on the same bumps.
Anyone seen an adjustment procedure?

Mandrake · Post by **Mandrake** » 26 Jul 2005, 12:56

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by xantiav6

<blockquote id="quote">quote:<hr height="1" noshade id="quote"> finding a good place to tap into the signal to the solenoids without splicing wires etc, and neatly running some wires back to inside the cabin and finding a good place to put an LED (either temporarily or permanently) is a bit more difficult than I thought.<hr height="1" noshade id="quote"></blockquote id="quote">
I did this by splicing into the wires to the front valve, but doing it where the splice is covered by the plastic sleeving when finished. The wire, I just ran up over the transmission and taped a small 12V bulb to the wiper blade. No need to thread wires into the cabin.
<hr height="1" noshade id="quote"></blockquote id="quote">
Sounds a bit hard case [:D] I was planning to do something a bit more tidy/permanent. Are you sure the bulb doesn't draw too much current and affect the proper operation ? Thats one reason I'd choose an LED, much lower current consumption...
<blockquote id="quote">quote:<hr height="1" noshade id="quote">
One problem that I suspect my current car has is that this motion sensor of the front roll bar is a bit sensitive, so when gong over a big speed bump, the front goes over in soft mode, but decides the bump was too big, and switches to hard mode befor the back wheels hit it. My previous car did not do that on the same bumps.
<hr height="1" noshade id="quote"></blockquote id="quote">
I suspect my car is doing something similar as well. On my street are some of those very wide fairly high judder bumps, and if I go over them at speed it actually feels like the hard mode is being triggered half way over the bump, causing a delayed "thud" when the suspension suddenly gets hard part way over the bump.
Until I hook up the LED I won't be able to tell for sure though.
<blockquote id="quote">quote:<hr height="1" noshade id="quote">
Anyone seen an adjustment procedure?
<hr height="1" noshade id="quote"></blockquote id="quote">
I doubt there is any way to adjust it. From what I've read its just a standard slotted disk optical quadrature detector, so there wont be any sensitivity adjustment.
If the LED's are not physically aligned to be at 90 degrees with that type of sensor however, it can cause erratic pulses, or cause the computer not to know which way it's turning, only that its turning...
Without being able to measure the direct output of the sensor I can't see any easy way of diagnosing it though...
Maybe the roll bar sensor of your previous car just wasn't working ?
Regards,
Simon

bernie · Post by **bernie** » 26 Jul 2005, 16:52

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by Mandrake

The way I see it there are 3 aspects of the suspension that need testing to fully diagnose a Hydractive 2 system, which is what I'll be doing:
1) Sphere pressures need checking...the best way to do this is a pressure tester, of course not everyone has one, but I have the bits to make one up again.
Because you have both corner spheres and a centre sphere its possible for one or the other to be almost flat and not easily be able to tell which, without doing proper pressure testing of each sphere.
Without the spheres being in good condition the computer and solenoids can't do their job...
2) Checking that the computer is receiving the sensor inputs and correctly making hard/soft decisions based on those inputs. The only way I can see of doing this is to somehow wire up an LED (and resistor) to the hydractive solenoid signal and putting that LED in the cabin where its easy to see while driving, so that you can evaluate the response of the computer to various stimulus.
(For example hard braking, vigourous acceleration, hard cornering etc should all trigger a switch to hard mode for a second or so)
This is easy in principle, but finding a good place to tap into the signal to the solenoids without splicing wires etc, and neatly running some wires back to inside the cabin and finding a good place to put an LED (either temporarily or permanently) is a bit more difficult than I thought.
3) Once sphere pressures are confirmed to be good, and the computer is sending the right signals, the remaining possible problem is that the solenoid doesn't actually switch when a voltage is applied to it, or (as I suspect in my case) doesn't always switch reliably.
Telling if this is the case is a bit tricky, basically you'd have to drive the car over a variety of surfaces comparing what mode the LED says the suspension is in, and how it feels. Also doing a stationary bounce test.
Regards,
Simon
<hr height="1" noshade id="quote"></blockquote id="quote">
I am in total agreement Mandrake.
I think a good idea would be to pool all our resources, testing and results etc.
We should be able to crack this between us.

Mandrake · Post by **Mandrake** » 26 Jul 2005, 17:20

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by bernie
I am in total agreement Mandrake.
I think a good idea would be to pool all our resources, testing and results etc.
We should be able to crack this between us.
<hr height="1" noshade id="quote"></blockquote id="quote">
One thing that I notice the Hydractive system on my car is doing that doesn't tally with expectation based on theory is this little test that I concocted:
1) Lift the car height right up, all doors closed, (so as not to trigger the open door switch which sends a signal to the computer) drivers window right down, then turn off the key, and wait for the 30 second timeout for the solenoids to drop out back to hard mode. (Audible click, and whining noise stops)
2) Then immediately lower the height lever to normal WITHOUT opening the door. The car should go down to normal height, but we have trapped the full 170 bar regulator pressure in the hydractive spheres.
3) Finally, key still off, open the drivers door. As soon as the solenoids switch on, there SHOULD be a sudden jump in height of the car, as the excess pressure out of the hydractive sphere is dumped back into the main suspension spheres, but on my car it DOES NOT. I can clearly hear the solenoids whining continuously when I open the door, but there is no jump.
However, when I turn the key on and start the motor, about 2 seconds later both front and back will suddenly jump up about 3 inches, (then correct back down to normal height) which is what I was expecting by simply opening the door.
My conclusion from this is that despite the solenoids being energized, the hydractive blocks are not actually being switched back into soft mode. The only reason I can think of this being the case is that there is not enough main pressure regulator pressure left to move the hydractive control valve despite the solenoid being activated.
To add some weight to this theory, I DO suspect the accumulator sphere is nearly dead on this car - it fails to do a sit in the boot lift test, and yet there is no audible rapid cycling of the regulator cutout noise...until I get a chance to do some more testing, or do a pressure test on the accumulator sphere, I won't know for sure, but I'm now suspecting that a bad accumulator sphere could upset the switching of the hydractive valves, at least when the engine is off anyway...
How much significance this might have to hard/soft switching while the engine is running (if any) is unknown however...perhaps at worst it will just slow down the hard to soft transition time...
Anyone got any ideas ? Anyone else care to try my test and see if the car jumps when the door is opened, as I think it should ? Or does it only jump after starting the engine ? (Implying not enough regulator pressure to open the anti-sink valves and/or operate the hydractive control valves..)
More info as I figure it out...
Regards
Simon

jeremy · Post by **jeremy** » 26 Jul 2005, 23:31

And there I was thinking that due to an imminent career change my BXTD estate and the ZX would have to go and I'd get a Xantia estate or more likely a C5. Looks like I'll have to invest a few pence in the BX and persuade my wife that its the best thing ever made!
Would I ever get the C5 working correctly?
Jeremy

bernie · Post by **bernie** » 26 Jul 2005, 23:33

I'll try on mine Simon.
One thing I've noticed on mine is the lhm feed to the rear solenoid is just drips.
I believe it's feed from the security valve if I can find it.
Yesterday I swopped the rear HA sphere for another.
I then started it up and it pumped to max. height, I opened the door and immediatly sunk to the floor. Now the door obviously operated the solenoid that opened the ha block and the ha sphere took all the pressure from the rear.
BUT I could hear the solenoids when I turned on the ignition so surely the ha sphere should have been filling also. Very strange.
I'm going to experiment with opening the door whilst driving slowly over speed ramps. At present it's awful going over bumps slowly.
Ill keep posting

alexx · Post by **alexx** » 27 Jul 2005, 00:33

HA2 Speed sensor ?