XANTIA ECU HELP

[davygr22]

Hope someone can help - my Xantia Hdi Exclusive is stuck in 'firm mode' & I'm running out of ideas!! All spheres have just been renewed,diode mod kit fitted,new VN05N components soldered onto PCB etc. Local dealer tried to connect suspension ECU to Lexia but could not get dialogue,so no idea if faults logged -tried ECU from another Xantia which I am assured was operational -but nothing!!
Electrovalve leak test done & seems fine - vehicle holds pressure well overnight & stop light extinguishes instantly on start up.
Tried electrical test at electrovalve plug using 100ohm resistor - no voltage at all.
Sport switch doesn't appear to have any power as when depressed the little warning lamp does not come on.
Vehicle has only done 67k & has decent maintenance record - recent Hydraflush & new LHM,return filters cleaned(were very clear).
Is there any way to electrically test the ECU off the vehicle ?
I dearly want to restore 'soft' mode - never had this issue on any of my former Hydractive Xantias!!!!

[Mandrake]

Have you checked the supply voltage going into the ECU ? It sounds pretty clear from what you've said, especially the substitute box not working either, that it's not getting any power. Is the main fuse that supplies it ok ?

It's in the under bonnet group near the battery. Not sure which number as I think it does vary from model to model, so check the owners manual.

On the ECU plugs pins 1 and 2 on the black connector are +12v input from the fuse box, and pin 5 is +12v supplied via the ignition switch. (So it knows when the car is running) On the white plug pins 8 and 15 are Earth.

If you're unplugging the connectors always make sure you disconnect the battery first, once unplugged reconnect the battery and measure the above pins to see if there is any supply.

More info here, including the full connector pinouts:

http://homepages.igrin.co.nz/simon/imag ... dractive2/" onclick="window.open(this.href);return false;

[Peter.N.]

I have had problems on the XM with corrosion of the wires under the engine fuse box, caused ABS failure on one.

Peter

[davygr22]

IT'S FIXED !!!! Thanks to everyone who posted - the issue was electrical - more precisely the main power feed on terminals 1 & 2 to the black ECU plug were providing no voltage - pin 5 which is ignition controlled was ok. Rather than trying to find where the power wire was damaged,I cut the two thick red wires at the
ECU black plug & spliced in a new fuse protected permanent +ve feed to the two wires & thus provided power to the ECU.(the way it should be)
As soon as I reconnected the battery & opened the door - on came both electrovalves !!!The sport switch warning lamp now illuminates when the button is engaged
and I've just had a brief test run to enjoy the fully operational 'soft ' mode suspension.
NEVER GIVE UP ON A XANTIA !!!

[Peter.N.]

Well done!

[taffy]

Lovely ending