Suspension Sensors Cause Hard Setting?, Can a failed steering sensor cause.....

I have theory to share with you all to see if there is any merit in it.
If the sensor on the steering or any of the body attitude sensors fails would this activate the default setting of hard mode?
I ask because my estate is nice and soft until I turn the steering wheel when doing in excess of 15 mph. It then changes to hard and stays that way until I park up and switch off. Then it is soft again until I turn the wheel.
I have experimented on this one across a large car park and I am convinced that all is well until move the steering.
Does any of this make sense?
Robin

This post has been edited by Robin on March 02, 2007 05:53 pm

I think I would agree with you there Robin. Presumably it only takes one sensor to activate and put the suspension in hard mode and not a combination of sensors. If that particular sensor is faulty then it should be possible to hang on in hard mode and not release.

I think that a Citroen Dealer's diagnostic equipment would identify your problem more quickly and accurately than any amount of inspired guesses alhtough the test is not always perfect or totally comprehensive. At about £35 it would seem to be money sensibly invested, especially as it will produce a pinted report which can be studied at leisure.

Did you get anywhere with this Robin? I ask because I had hard suspension, got the spheres checked out (they were fine) and then asked the garage to run a diagnostic test; it registered a fault for the steering sensor, which, according to the invoice, the mechanic ``cleared and did not recur''. Ride's still hard though.

Matt

Have a look at e-crofting.com and consider investing in that cheap "suspension softener". It will not affect any other system and can be fitted or removed in a matter of minutes. ( Or leave it in place for the time when the diodes do fail and give a hard ride)

Coming back to this one again, I have not managed to get the fault codes read. I took it over to the local Cit Dealer and they confessed to never having worked on an XM before but if i left it with them they would have a go.
Sorry folks but they are not learning on my XM!
So I still have the intermittent hardness but experience does now tell me it is all speed related. Take it easy from starting off and all stays soft and supple but once over about 35 mph it then goes in to hard mode - most times.
Cheers all, Robin.

The locking in hard mode effect could be caused by a fault in the suspension ECU. If the fault clears after you switch the ignition off and then on again, the circuit could be latching for some reason - only a suggestion, but it doesn't take more than a few minutes to fit another ECU and there should be plenty of scrap ones about, or maybe you could borrow one.

Peter.N.

Robin, as it seems your problem is electronics-related, I think the best to do is really give it to them -or other dealer- for reading. I don't think they can harm it after all.

regards
George

Thanks George, Peter. I will have to get the unit read, I do not fancy trying to track out a suspect sensor on luck alone.
The ECU has been given the loving attention of new diodes and these improved matters which how I came across this other problem. It is not consistent or a problem. the other matter of course is only driving my own XM and the other comparisons I get to drive are my Porsche, a Vauxhall van and a pre facelift Xantia which is firmer than the XM naturally even in hard mode.
I understand the car changes from soft to hard depending on the driving style and body attitudes coming back to soft when cruising straight and level.
If this is so then my XM may be behaving more or less correctly. Changing from Norm to Sport does alter things - I am sure I think

I am off to Wolsey House Motors on the 19th to get the Xantia looked at and this will need a new clutch soon too. I will ask them to read the suspension ECU if they have the time and will report back.
Best wishes all, Robin.

Hi Robin

If its a Mk2 you wont notice any difference in sport mode initially, because unlike the Mk1 the switch doesn't overide the ecu, it just makes it more sensitive so that it goes into hard mode with less provocation. Driving in a straight line you will feel no difference.

Peter.N.

It is a Mk 2 Peter so just possibly I am worrying without cause. I have a favourite stretch of bendy road, about four miles of it, which is wonderful to drive and I can certainly tell when the sport mode is working on that compared with norm. As you say it makes the car that bit more responsive and ready to correct roll and pitch.
I have so far caused even a Mazda sports to back off in a duel for the end and many other standard motors - such fun overtaking them in their braking zone and whipping through the corner with a motor as big as an XM.
My next main job is to hush the annoying rattle from the height control lever. The rod has come adrift I think from its antirattle spring below next to the exhaust. If its not that then it is at the ends, probably front, where a bit of wear has taken place. I can stop the minor rattle by moving the lever very slightly from the normal position either lower or higher and it is quite surprising how much difference even this tiny movement makes to the ride height fore and aft.
It also affects the ride comfort too which just proves how important the height geometry is.

I just need it to stop raining at a time when I can do the job!

Cheers all, Robin.

Hi Robin

You will probably find that your exhaust has moved, as its very close to the height control linkage. If you undo the clamp in the centre, you should be able to rotate the front pipe away from it.

There is a very interesting video clip by Tiff Nedell showing the handling capabilities of the XM which hopefully you should find at this link.


http://www.youtube.com/watch?v=2DN9Rbs8V88

Peter.N.

Seen it - wonderful stuff. 3 cheers to Citroen