Sport mode after running Lexia

[Edhertz]

The yellow fault indicator came on recently. Carried out the Lexia function and global tests to see what was causing it. Laptop started to play up so aborted the test part way through. Went on my merry way to find that my normal comfortable ride had become significantly harder. Sorted out the laptop and carried out Lexia tests again to find log of different faults among them 'permanent faults - ECU, front electro valve and rear electro valve'. I noted the faults and reset to clear indicator. Car has been run several times with the faults present and indicator has not come on. Is this normal? Reading the various forum threads leads me to conclude that it could be a failure of the coil flywheel diodes, sorted by the 'diode mod'. Anyone any ideas as to why running Lexia should make the suspension go into sport mode? Finally am I right in saying the ECU is under the cover where the handbrake is?
Thanks for looking
'99 Xantia 2.0Hdi Exclusive

[Mandrake]

No its in the Engine ECU plastic box in the engine bay near the front right headlight. It's the module with the two connectors, one black and one white.

I can't really see how your Lexia session could have done anything as the Hydractive ECU tests are all passive, apart from clearing fault codes. Have you tried disconnecting the battery for 15 minutes ?

[CitroJim]

There is definitely an electrovalve problem and most likely it'll be resolved with the diode mod. There's no harm in doing it anyway..

What I think may have happened is that before the diagnostic the valves were happily stuck in soft mode, which does occasionally happen, and you doing a diagnostic has disturbed them and they've flipped back to the hard position.

Do the diode mod, clear the faults and see how they go.

When all is goo you'll hear the electrovalves turn off with a good solid click at the end.

To test, start the car, wait for fully system pressure to be established and correct height to be achieved. Then switch off and bounce both ends. Both should be soft as the system is presently in soft mode. Make sure all doors and tailgate are shut and then carry on bouncing. After 30s the ECU will time out and switch to hard mode. You should hear a good solid click from each valve and feel a definite stiffening in the suspension.

Opening a door should;d cause a switch to soft mode again accompanied by a click from the valves and a soft humming noise which will carry on until the valves switch hard again.

[Edhertz]

Car 'diode modded' today and what a difference! It behaves exactly as you describe Jim with only one difference. When I first got the car it made a definite loud 'clonk' as the solenoids dropped out. It has been replaced with a gentle but positive 'click'. So overall a happy bunny. Will clear faults tomorrow and have another look after a bit of running around. Thanks
everyone for your replies as always.

[KevMayer]

Excellent result.

[CitroJim]

That's brilliant news Ed