v6 Hydractive queries

jgra1 · Post by **jgra1** » 15 May 2006, 14:23

Guys, how long does it take for your suspension the stiffen up after pressing the button, likewise doing the opposite?

Does the system pressurise all four corners? on mine the back end is still soft after pressing the button, and also, once the front is firm it seems difficult to get it back to soft again, after depressing button one more time..?

John

Quackers · Post by **Quackers** » 15 May 2006, 14:45

On my V6 it seems to take less than 5 seconds. Somthing sounds wrong with yours.

Post by **RichardW** » 15 May 2006, 14:49

John,

The button does not switch the car between hard and soft modes - all it does is make it easier to get the computer to swich it into hard mode when Sport mode is selected. To check the difference between hard and soft mode, push it down with the engine idling - this should be soft mode. Now switch off, close the doors and wait for it to stop humming (approx 30s). If you now push it down it should have notable stiffened. In soft mode it should be very soft - an easy 4-6" of soft travel.

There seems to be a variety of problems with hydractive cars related to the electrovalves. Let us know what you find!

andmcit · Post by **andmcit** » 15 May 2006, 14:52

First off the change should be instant [either way] - after all you've just clicked a new parameter for the ECU's working range. This IS supposed to work in microseconds...

Mind, there's really no need to use the sport setting - unless you want to feel like you're in a Mazda or Bmw...

The car should STILL be reasonably soft! There will be movement on the corner spheres if they're 100% - the altered parameters for tautening up via the closed centre spheres will only be really apparent when you're hooning about!!

Does sound like the pair of electrovalves are independently doing their thing without much harmony...

Andrew

jgra1 · Post by **jgra1** » 15 May 2006, 15:46

thanks all..

where to begin..

ok, I do like the feel of the car when the front is stiffened up

i live in a very curvy part of Sussex, and do drive spiritedly after pressing the S butttons

I have a feeling the front spheres need changing, becuase at no time are they as supple as my 1.8 Xantias were.. I can push them down, but need about twice the force than i am used to.

It seemed like I pressed the S button, as pushed all corners, the back remained soft throughtout all the test. The front began soft (ish) and would not stiffen even after some time with car idleing. I depressed the S button and tried again, and then the front is hard! (could have been a coincidence) The back is still soft...

then, I waited with S off, to see if the front would soften, it wouldnt. I think I turned engine off eventually and still front is tough. I restarted the car, still tough. I let suspension full down and full up and back to normal.. It seemed then that the front was softer....

To be honest, the car drives very well.. whether button is activated or not, it feels like a good compromise between a too firm ride and the soft ride of my 1.8... I was just curious to try and make it all happen at idleing
speed.. but looks like I have uncovered something not quite right...

The button does not switch the car between hard and soft modes - all it does is make it easier to get the computer to swich it into hard mode when Sport mode is selected.

Richard sorry can you explain this one more time

he car should STILL be reasonably soft!

I am 100% the back end is lovely and soft in either mode.. cant detect any change at all.. can anyone confirm theirs is noticeable?

Post by **RichardW** » 15 May 2006, 16:18

Hydractive has 2 modes - hard and soft - and which are nothing to do with the swtich in the car

. In Hard the centre spheres are isolated and springing is provided only by the corner spheres, and, since the spheres are isloated from one another, roll is reduced. In soft mode the centre sphere is connected, and the suspension should be nice and soft. Hard and soft is determined by the hydractive computer energising / denergising the solenoids in the hydractive blocks - that which the centre 'hydractive' spheres screw onto - when energised the car is in soft mode. In soft the car is softer than a normal Xantia, and in hard, considerably stiffer. The computer decides when to apply hard mode depending on a number of inputs, including pedal position, steering position, steering rate of rotation, body roll etc. Since de-energised is hard mode, this is the mode you get when the car is not being used - however, when you open a door it selects soft mode - you should hear the hydractive valves whining / humming. Inside the car there is a suspension switch which has 'Comfort' and 'Sport' positions - in sport mode the parameters that lead the car to select hard mode are reduced - eg less steering, less body roll etc. In the original hydractive XMs it did permanently select hard mode, but that was way too hard, hence the mods to make it increase the sensitivity - it's really a redundant gimmick, as I'm sure they could have programmed the ECU to learn if you were throwing it about and engage hard mode sooner.

So the only way you can 'force' hard mode is by shutting the car down, shutting the doors and waiting for the hydractive valves to shut down - pressing the switch makes no difference at all unless the car is in motion.

I run mine in comfort now - it seems to give less trouble that way, and gives hard plenty soon enough if you're having a hooligan day!

I'm kind of on the look out for an HDi, but I want an Exclusive, since I think the hydractive is better.

jgra1 · Post by **jgra1** » 15 May 2006, 16:35

Richard, many thanks

Well... i have had this one for a week or so.. maybe I should have held out for an Hdi .. but its great fun.

Still very keen to LPG it... will let you know.. The idea was I had a third button, an LPG / Optimax (or similar) button

J

one more question. When car is cold, it holds first gear till about 3000.. when warm it changes much earlier.. is this another useful feature, which wont let the engine labour when cold?

Post by **xantia_v6** » 15 May 2006, 22:03

jgra1 wrote: one more question. When car is cold, it holds first gear till about 3000.. when warm it changes much earlier.. is this another useful feature, which wont let the engine labour when cold?

According to the literature, this behaviour is not for the benefit of the engine, but to get the transmission fluid warmed up as quickly as possible. I find it quite irritating.

BTW, an interesting test for the HA suspension is to find an empty road where you can use 2 lanes without being too conspicuous, put the suspension into comfort mode, and at around 40 MPH sart weaving gently from side to side, increasing the movement until you can feel a bit of body roll. Then while still weaving, hit the switch, and the car should tighten up as the computer switches to sport mode.

regards,
Mike

jgra1 · Post by **jgra1** » 15 May 2006, 22:07

Mike, thanks, will try that very soon!

yes I am not for the long gearchange really.. I am all for giving the engine an easy time when cold, but 3000 rom just feels a bit too high... I think ICE mode may be a work around

J

Stempy · Post by **Stempy** » 16 May 2006, 11:24

Just a thought, but if you remove the fuse that supplies the HA ECU then the car will be permanently stuck in hard mode, even at a standstill, as there will be no current to energise the solenoids into soft.

Mandrake · Post by **Mandrake** » 16 May 2006, 11:36

Stempy wrote:Just a thought, but if you remove the fuse that supplies the HA ECU then the car will be permanently stuck in hard mode, even at a standstill, as there will be no current to energise the solenoids into soft.

Yep, that works.

As long as you can positively identify the right fuse! (It is in the owners handbook, but there are a lot of variations of the fuse holders across the years....)

And if you go for a drive with the fuse removed you'll see why Citroen ditched the idea of the Sport mode switching permanently to hard mode in Hydractive 2!

(Above 30Km/hr)

(Let's just say, you'll feel like you've been in a saddle, not a seat when you get back...

)

Regards,
Simon

bernie · Post by **bernie** » 16 May 2006, 14:30

Stempy wrote:Just a thought, but if you remove the fuse that supplies the HA ECU then the car will be permanently stuck in hard mode, even at a standstill, as there will be no current to energise the solenoids into soft.

As well as disabling the HA2 circuit, the fuse also powers the central locking/alarm and interior lights

Mandrake · Post by **Mandrake** » 16 May 2006, 20:53

bernie wrote:
Stempy wrote:Just a thought, but if you remove the fuse that supplies the HA ECU then the car will be permanently stuck in hard mode, even at a standstill, as there will be no current to energise the solenoids into soft.
As well as disabling the HA2 circuit, the fuse also powers the central locking/alarm and interior lights

Not on my car it doesn't! I guess that illustrates the variations in the fuse box wiring that occured over the years...on mine there is a dedicated fuse for the Hydractive computer that doesn't affect anything else.

Regards,
Simon