2.1 auto m reg exclusive

[CitroJim]

Doesn't that indicate the lamp is duff?

Not necessarily so as the bulb is driven by the ECU, not the switch. This enables the lamp to perform a limited diagnostic function.

We found the Team WFA 2.5 had been 'modded' in the Hydractive department to hold the electrovalves open and the suspension in permanent soft mode.

Here's the evidence:




After replacing all the ruptured spheres (most of them!) I took it for a drive before putting the ECU wiring back to normal and doing the diode mod.

In permanent soft mode the handling is truly atrocious. It rolls like a barrel. After undoing the bodges and clearing the faults in the ECU handling was transformed...

[Dieselman]

So it was modified for the sake of a couple of 30p diodes.

[CitroJim]

So it was modified for the sake of a couple of 30p diodes.

Yes, and a read and clear of stored faults. What amazes me is how the electrovalves themselves survive constant 12v for such an extended period. It was always believed they were driven by a pulsed signal of just sufficient amplitude to hold them operated because they would rapidly burn out if subjected to full 12v for any length of time. Normally they have just half a second of full 12v applied to them to operate them before the pulsed signal is applied to hold them operated.

These two at least have survived unscathed... They're tougher than we thought.

[russ92xmsed]

Eeeek when you put it like that Jim, I really need to sort mine out. So if my diodes have packed up, which is a possibility, what is the fixing procedure on a hydractive 1 car with one electrovalve. As it isn't as easy as fitting the e crofting device is it?

Is it a matter of soldering in new ones on the suspension ECU circuit board.

[xmexclusive]

Early Mk1 electrovalves (there were two different designs) were to a totally different design to the later Hydractive 11 types that Citroen used as standard from 1993 on.
As far as I know no one has checked if or where the circuit has a diode.
The early ECU's and prototype electrovalves are supposed to be bomb proof compared to the later Hydractive 11 offerings.
What I have seen of the diodes and drivers in the ECU's confirms this.
So as far as I know no one bothers to recover these components from scrap cars.
I seriously doubt these components will be the cause of your suspension problem.
Testing your system to fault find will need a separate approach and instructions.
Not seen anyone document them here.

John

[russ92xmsed]

I see. Thanks John for explaining that. So hence why no e crofting for S1 and no obvious info about fixing them.

[Dieselman]

If your car is locked in hard mode it is likely to be either a sensor or ECU fault, the sensor being the most likely.

[Eddie nuff]

The engineer/mechanic who kept mine on the road for 10 years told me he had the circuit board out and repaired and re-soldered everything.

[russ92xmsed]

Wow.. he was brave!

Not sure if it is locked in hard mode yet, but due to the wires having been cut, seems to point towards that. ECU talks to Jims lexia and it does what it is meant to. But full tests to be carried out soon.
I have a feeling it is low system pressure. From what the front does when it is in full height mode, might point towards the culprit.

[CitroJim]

ECU talks to Jims lexia and it does what it is meant to. But full tests to be carried out soon.

I've never properly worked on an H1 system, all my experience is with H2. That said I'm really looking forward to seeing what we can do to sort out yours Russ...

Low system pressure can certainly upset H2 systems. I have seen it low enough that the anti-sink valves pop into operation when vigorously bouncing the suspension and make the suspension go rather hard. It can though cause H2 systems to be sluggish to switch to soft as the electrovalves rely on both pressure and an electrical signal to switch - one assists the other.

Russ, I may be able to check system pressure with my tee-gauge if there's enough room around your pressure regulator.