Hydractive Electrovalves rebuildable?

[ekaftan]

I replaced the spheres on my VSX thats stuck on hard mode. I also
reset the HA2 ECU and it seems to be dead.

Car is barely drivable, but at least is not rock solid now.

Only thing left to try, before replacing HA2 ECU, is to see if the diode is bad on the valves. Valves work when supplied with 12 volts but ECU wont activate them.,

Are the valves fixable?

How much are they new? used?

[KP]

Someone on hre was breaking a VSX so maybe worth just getting used valves off them and cleaning them up and a spare ecu as well as you never know when you may need it...
I think it was Phil Howard selling the bits

[citronut]

which spheres did you replace,because GSF recomend when fitting new spheres at the rear to replace the center sphere at the same time,otherwise you could still end up will hard suspetion
regards malcolm

[Mandrake]

I replaced the spheres on my VSX thats stuck on hard mode. I also
reset the HA2 ECU and it seems to be dead.

Car is barely drivable, but at least is not rock solid now.

Only thing left to try, before replacing HA2 ECU, is to see if the diode is bad on the valves. Valves work when supplied with 12 volts but ECU wont activate them.,

Ok, so you do get a much softer bounce test at each end when you manually apply 12v to the valves ? Did you try my trick with the 15 ohm resistor ?

If you apply 12v and the valve switches on, and then you let it drop back to 3v dropped via the resistor after the clip is removed, (dont let the power drop off even for a moment while doing this) does the valve STAY activated ? If it does, the mechanical part of it is ok. It's important that the valve can stay activated in the soft mode when the voltage drops to 3v, because that is what the computer does...

Did you try the test I outlined for testing the internal diodes ? All it requires is a multimeter and the 15 ohm resistor and it will tell you for sure whether the diodes are faulty.....

Are the valves fixable?

They can be stripped down but it is quite difficult because there is a lot of locktite on the internal thread making dissassembly a risky process - anyway, one thing that you CAN'T get to is the diode... its in the middle of the moulded plastic coil section.

How much are they new? used?

New they are very expensive In the UK they are about 100 pounds each...

I strongly suggest you have a good thorough read of the following thread before going any further:

http://www.frenchcarforum.co.uk/forum/v ... hp?t=18803

It covers both electrovalve dissassembly (which you probably don't need to do) and the fitting of external diodes as a workaround.

Regards,
Simon

[Mandrake]

which spheres did you replace,because GSF recomend when fitting new spheres at the rear to replace the center sphere at the same time,otherwise you could still end up will hard suspetion
regards malcolm

In the original message thread we established that the centre spheres were ok...(the car jumps nearly a foot when the electrovalve momentarily activates, something it wouldn't do if there wasn't much gas in the centre spheres)

Regards,
Simon

[ekaftan]

Ok, so you do get a much softer bounce test at each end when you manually apply 12v to the valves ? Did you try my trick with the 15 ohm resistor ?

Yes to a much softer bounce, no to the 15ohm resistor trick. Will read you orginal post again and try it tomorrow. Today I could not get the white connector from the HA2 ECU due to lack of tools. Can you remind me which pins are the white wires connected to?

If you apply 12v and the valve switches on, and then you let it drop back to 3v dropped via the resistor after the clip is removed, (dont let the power drop off even for a moment while doing this) does the valve STAY activated ? If it does, the mechanical part of it is ok. It's important that the valve can stay activated in the soft mode when the voltage drops to 3v, because that is what the computer does...

Did you try the test I outlined for testing the internal diodes ? All it requires is a multimeter and the 15 ohm resistor and it will tell you for sure whether the diodes are faulty.....

I will try that tomorrow.

One thing I did today was replacing the fuse to the ECU with a dummi one in series with an ammeter. I read .136 amp with engine stopped and doors closed. It jumped to over 1 amp when a door was open, so I am assuming the HA2 ECU is not completly dead after all.

I also measured the resistance from the white wires to earth and got exactly 4.9ohms for each one. I also reseated and cleaned both connectors.

I tried to get a voltage reading form the wires but failed. Maybe my tester is too slow to read the test pulse.

Will try the diode test tomorrow and report...

The car with 4 new spheres is at least drivable.... Front ones were weak but still had some gas in them. Rear ones were marked 'front' AND LHM level dropped almost a liter after replacing them so they were completly shot.

[Mandrake]

Yes to a much softer bounce, no to the 15ohm resistor trick. Will read you orginal post again and try it tomorrow. Today I could not get the white connector from the HA2 ECU due to lack of tools. Can you remind me which pins are the white wires connected to?

To unplug the white connector you need to locate the wire clip which goes around 3 sides of the plug, a small flat blade screwdriver is all thats needed to prise it out. Pin 1 is front, Pin 2 is rear, and pins 8 and 15 are earth.

One thing I did today was replacing the fuse to the ECU with a dummi one in series with an ammeter. I read .136 amp with engine stopped and doors closed. It jumped to over 1 amp when a door was open, so I am assuming the HA2 ECU is not completly dead after all.

Unlikely to be completely dead, but I'm just hoping that the hotwiring that was there didn't blow up one of the output transistors!

I also measured the resistance from the white wires to earth and got exactly 4.9ohms for each one. I also reseated and cleaned both connectors.

Ok, 4.9 ohms seems slightly high, but that includes the resistance of the cabling, so its probably about right.

I tried to get a voltage reading form the wires but failed. Maybe my tester is too slow to read the test pulse.

Yeah possibly, a good old analog voltmeter is good for this! Some cheap digital meters wont read PWM waveforms even as low as 1Khz.

Will try the diode test tomorrow and report...

The car with 4 new spheres is at least drivable.... Front ones were weak but still had some gas in them. Rear ones were marked 'front' AND LHM level dropped almost a liter after replacing them so they were completly shot.

Sounds like this car has had a checkered past....

Regards,
Simon

[ekaftan]

Unlikely to be completely dead, but I'm just hoping that the hotwiring that was there didn't blow up one of the output transistors!

That I can fix... I have access to a very good electronics tech (I have a can-audio shop as a second business) so thats not a problem if the HA2 ECU is not completly sealed...

Sounds like this car has had a checkered past....

Its just the local way of doing this. 90% of Chilean mechanics have this 'fix it with duct tape and barb wire' mentality.

I bought the diodes (4, I will add them to my 96 Xantia also, I am starting to have strange 1 foot jumps in it also) and a couple of leds to make test
probes.

How did you connect the led? Do I need to add a resistance or just connect it in paralel to the valve wiring?

[Mandrake]

That I can fix... I have access to a very good electronics tech (I have a can-audio shop as a second business) so thats not a problem if the HA2 ECU is not completly sealed...

Ok thats good. I've definately seen some pictures of a Hydractive 2 ECU disassembled, I'll see if I can find them for you... it's possible just the output transistors are damaged.

Ah, here we go:

http://membres.lycos.fr/ci6web/auto/activa/

Have a look at the pictures named "calculo susp diodes" 1 through 8.

Sounds like this car has had a checkered past....

Its just the local way of doing this. 90% of Chilean mechanics have this 'fix it with duct tape and barb wire' mentality.

I bought the diodes (4, I will add them to my 96 Xantia also, I am starting to have strange 1 foot jumps in it also) and a couple of leds to make test
probes.

How did you connect the led? Do I need to add a resistance or just connect it in paralel to the valve wiring?

The LED needs about a 100 ohms series resistor - I used a rectangular high intensity green one, (to be able to see it from the corner of my eye while driving, mounted at the top of the dashboard near the drivers door) and connected it to the front electrovalve signal (or the one you're testing) and earth.

(Under normal conditions both front and rear turn on and off together, even though they are seperate circuits)



Normally when it switches from hard to soft you'll see the LED come on bright for half a second (full 12v) then slightly dimmer after that (3v PWM) which is normal behaviour.

I suspect what you'll see is bright for half a second then off again.

If the computer detects an improper load it does the half second 12v part of normal activation, then switches the outputs off again for exactly 60 seconds, thinking there is a fault, and it will then try again for half a second, if the fault still exists it will turn off for another 60 seconds and so on....each time it does this if the load has changed in the car there is a potential for the suspension height to jump.

Also, if there is a fault with ONE electrovalve, the computer will switch BOTH valves off during this 60 second time as a safety feature. (The car's handling is less safe if one end is hard and the other is soft, for example soft at the front and hard at the rear can even provoke some oversteer in hard cornering)

Regards,
Simon

[ekaftan]

That I can fix... I have access to a very good electronics tech (I have a can-audio shop as a second business) so thats not a problem if the HA2 ECU is not completly sealed...

Ok thats good. I've definately seen some pictures of a Hydractive 2 ECU disassembled, I'll see if I can find them for you... it's possible just the output transistors are damaged.

Update:

I tested both electrovalves with your method. Both open with 12volts direct but don't stay open when fed with the resistor.

I then added the diodes to the cabling and the test failed again.

Thats when I realized the electronics shop salesman had given me 15Kohm resistors instead of 15ohm. Of course, too late to go change them.

Anyway, I disassembled the HA2 ECU and found no obvious damage. No burned parts. No bad looking joints.

I reassembled everything but it still does not work.

The ECU never gives 12volts to the valves so a burned output stage is the most likely scenario but I could not find the damage.

A new HA2 ECU seems to be the way to go. I'll keep an eye for one for sale or wait for one of you to break a VSX

[bernie]

The ECU never gives 12volts to the valves so a burned output stage is the most likely scenario but I could not find the damage.


You wont see 12v going to the valves because it is very quick before it settles back to 3v.

I suggest a diode will do the trick, remember they are polarity conscious.

[ekaftan]

The ECU never gives 12volts to the valves so a burned output stage is the most likely scenario but I could not find the damage.


You wont see 12v going to the valves because it is very quick before it settles back to 3v.

I suggest a diode will do the trick, remember they are polarity conscious.

No 12, no 3...

I will have to get the car hooked up to a scanner and see if the HA2 ECU gives error codes.

Diodes are in place al ready and got no change.

[bernie]

The ECU never gives 12volts to the valves so a burned output stage is the most likely scenario but I could not find the damage.


You wont see 12v going to the valves because it is very quick before it settles back to 3v.

I suggest a diode will do the trick, remember they are polarity conscious.

No 12, no 3...

Ah... not good

I have a spare HA ECU, where are you?

[ekaftan]

Ah... not good

I have a spare HA ECU, where are you?

Santiago de Chile.

But I have a forwarding address in the US you can send something to.

Switch to email for details?

[bernie]

Ah... not good

I have a spare HA ECU, where are you?

Santiago de Chile.

But I have a forwarding address in the US you can send something to.

Switch to email for details?

Sorry ekaftan, if you were local to me I may have been able to help