Citroen XM Forum

Been looking at this with interest, as the badges on mine are worn. I was wandering if one of those gloss detail rollers would do the trick, although it would be quite wasteful on paint. Not high on my list of priorities - I think the black badges adds to it's 'stealth bomber' look!

22 years of grot here and the beginnings of rust.

Although I never removed the mudflaps I did regularly clean out behind the wheel arch liners Graeme and that lower wing is in pretty good nick! Most of my cars have needed replacement sections and you even have the bracket still in place! I have repainted wing badges using the sponge and fine brush technique and a combination of the two is quite successful. With regards, Matthew T.

Hydractive updates!

The engine fault codes remain at bay although it still doesn't run well. It's the hydractive that's still playing up. Fault code 24 again: vehicle speed sensor. It'll always start off fully functional switching in and out of hard mode but within a mile it goes hard and stays that way until it's restarted.

I tried dean's idea of connecting the other speed sensor up to the plug to drive without the sensor giving signals to the ecu but it doesn't make a difference it still comes up with the same fault code. As does disconnecting it to run without the sensor.

The chart of fault codes suggests the sensor should have a resistance reading of 300 ohm at its terminals and I find a reading of 270 on one of the sensors and278 on the spare sensor I'm borrowing of Mark at Xm central. If you open up the sensors the magnet within can be seen to have cracks in it (both sensors have this) but I'm not certain of this is the cause of the faults.

Anyway I'm certain this is the cause of the problem now so I on the hunt for a speed sensor for Swiss one XM if anyone has one up for grabs

Also measured the volts at the plug to the sensor and get 8.7v with engine on - not sure if this is what's expected or not?

As for the front wing - I spent ages on it but I'm not happy with the results so I'm going to replace the wing and get it painted - anyone have a driver side front wing for sale?

Needs most of the exhaust replaced too but at least that's fairly simple - just need to find one for the right money.

Rear subframe is rusting and the infamous rear mountains are looking like they'll need treated before they rot through so that's a weekend job.

8.7v sounds odd (unless it's the sensor output, which is variable). Later box-mounted distance (speed) sensors receive a 12v IGN supply, plus GND and Output connections. Could someone with an earlier circuit diagram (?? RP) check ?

I wondered whether the supply power was limited for one reason or other. I was sent a lot of the diagrams by xmexclusive but I'm not at home so can't check till later ( can't ' interpret' till later haha)

I suppose the power is supplied from the ecu output (?)

The later sensor is fed direct from a fused IGN supply - but check with the circuits John sent you.
Can you add your RP/Orga number to signature or profile. Will help a lot.

Yes will do that (might add the CX's too for a laugh)

Amazingly the hydractive performed properly for over a mile one occasion during the week! It hasn't repeated this however. I do wonder what temporarily fixed it. It was still in soft mode when I parked up- this never happens.

I decided to remove and clean the earth points on the inner wings. Every ring terminal cleaned, the face of the captive nut/ earth nut taken to bare metal and each terminal refitted with earth washers. The result...... No difference to anything but at least it's a little job of the list. Engine still runs a bit rough at idle and the hydractive still gives less than a mile of smooth.

I found the faulty vehicle speed sensor is being supplied with 8 volts - not certain if it's meant to be less than 12? But the earth pint revamps haven't changed that.

Exhaust system rebuild
Steering pinion leak
Front wing repair
Hydractive

That's the to do list!

I was looking through the excellent charts John sent but they are for the engine - I have nothing for the Hydractive wiring at all. Anyone (John?) got a Hydractive 1 wiring diagram? I really only need to find out how the speed sensor is fed i.e via a switched supply from something like the ignition or if it is fed a voltage from the ECU and the ECU reads what comes back.

It still reads as 8.7 volts supplied to the sensor.

White Exec wrote:8.7v sounds odd (unless it's the sensor output, which is variable). Later box-mounted distance (speed) sensors receive a 12v IGN supply, plus GND and Output connections. Could someone with an earlier circuit diagram (?? RP) check ?

It was measured at the disconnected plug of the speed sensor then the ignition switched on to find 8.7v. I think the other terminal - there's 2- is just going to earth as I buzzed it out and it had continuity to earth. Maybe it's not meant to? or maybe it gets continuity to earth via the earthed ECU (?) Also, as reported elsewhere, I rebuilt all of the engine bay earth points on the inner wings. Still get the same results though!

Can anyone help?

Series 1 cars with the speed sensor in the speedo cable have a small "electronics" box. I believe box just amplifies and converts the signal from the speed sensor into one that is useable by the various ECUs (hydractive, trip computer and possibly engine?). I had to replace this box on my XM when I first purchased it as it had failed - intermittently at first then completely no speed signal from it at all. It made the suspension stick in hard mode (hydractive 2). The box is located above the drivers knee and is the one with 9 pins.

Some Peugeots use the same box for their speedo, google "Peugeot speedo interface box" for some good info. Usually the issue with them is dry solder joints and some people have repaired them by resoldering all the joints.

Jordan.