I am also P£$$$ed with hydractive

[davetherave]

Club-xm is down so ill ask all xmites here!

My car starts a journey ok, but at some point in the journey chucks itself into hard mode, when I come to a stop and do the bounce tests, there is no movement at all it is just solid.
Is this likely to be down to the ECU?
If so could I use the ECU from my estate for testing purposes? I guess some parameters would be different, but if it saves me having to undergo spinal surgery!!
Dave

[DickieG]

Unless I'm mistaken all Hydractive 2 ECU's are the same it's the programming that is different and AFAIK there isn't a specific program for estates. I know that Xantia 1 and 2 ECU's aren't compatible as using a series 1 ECU in a 2 causes the suspension to switch to firm after 25ish MPH. One things for sure you won't cause damage by swapping the ECU's provided they are both from the same version of Hydractive as in Hydractive 1 or Hydractive 2.

IIRC you have a Lexia so why not use it to observe the state of the suspension?

[davetherave]

I have had the lexia on it whilst stationary and its fine.
When it goes in hard mode turning the ignition off and on breaks it out of it.
Hence I wonder if the ECU is at fault
I will have to try the estates ECU and see what happens!

[DickieG]

Have you used Lexia to check what programme the ECU has on it as in Xantia or XM? IIRC it's on the Hydractive perameters page.

[robert_e_smart]

Dave, when club Xm is back up, have a look at the threads I created when I modified my electrovalves to keep the car in soft. Its reversible, and certainly much better than having the car in hard all the time.

[Deanxm]

Check ecu's before swapping there were three versions of the Hydractive 1 and probably the same amount of versions for Hydractive2 suspension setups, on the case of the ecu there will be a small stamp marked H2 or H3 etc, this is the ecu version number.

D

[DickieG]

Check ecu's before swapping there were three versions of the Hydractive 1 and probably the same amount of versions for Hydractive2 suspension setups, on the case of the ecu there will be a small stamp marked H2 or H3 etc, this is the ecu version number.

In addition to that there isn't any way of knowing what software is loaded onto the ECU without using a Lexia to check it, dates may give a slight clue but no more than that.

[xmexclusive]

Hydractive 2 ECU's started as H4 then progressed to version H5.
It is only the H5 version that needs reading with the Lexia to determine the vehicle that it has been programmed for.
The H4 ECU's were hard coded at factory and are marked with supplementary letters to indicate vehicle type.
None of these ECU's can have their settings recoded by the Lexia.
All types have the same contact pin allocations so should work when swapped between vehicles.
The hard/soft switching may not be quite as designed by Citroen but will not be that far out.
The biggest risk in swapping ECU's is knowing their internal working condition.
If the solenoid drivers have problems this will just confuse fault finding.

John

[Deanxm]

It would be interesting to know what the differences are between the different versions of ECU's and what citroen thought needed changing, i guess its just switching perameters and different components used........................

D

[DickieG]

All types have the same contact pin allocations so should work when swapped between vehicles.
The hard/soft switching may not be quite as designed by Citroën but will not be that far out.

That's not entirely true as for the reasons I mentioned above.

[Deanxm]

All xm hydractive ecu types apart from H5 cannot be re flashed though, certainly with earlier ones they are completely different to later H4 and H5 versions with different electrovalve drivers, H1, H2 and H3 cannot be read with a lexia other than to extract fault codes from experience, odb just wasnt that far advanced when they were made, in all versions the case markings represent the ecu setup, i know on my activa and spare activa hydractive ecu these markings are different to my early xm ones, i want to get the activa on a lexia and see what you can do with the later ecu's.

D

[DickieG]

All xm hydractive ecu types apart from H5 cannot be re flashed though, certainly with earlier ones they are completely different to later H4 and H5 versions with different electrovalve drivers, H1, H2 and H3 cannot be read with a lexia other than to extract fault codes from experience, odb just wasnt that far advanced when they were made, in all versions the case markings represent the ecu setup, i know on my activa and spare activa hydractive ecu these markings are different to my early xm ones, i want to get the activa on a lexia and see what you can do with the later ecu's.

All you do with Hydractive 2 ECU's is read the datastream flowing to and from the ECU, clear codes and see what software has been loaded onto the ECU as in whether it was for a Xantia or XM, as mentioned above these ECU's (including H5) can only be loaded with software once.

[Deanxm]

Ah yes i believe they come bare dont they and can be flashed to be xm or xant cant they and then thats it.

D

[DickieG]

Ah yes i believe they come bare dont they and can be flashed to be xm or xant cant they and then thats it.

Yes that's it.

[addo]

I have confidence someone like John can figure out how to hoover up the code, and then clear the program.