My Citroen XM 3.0 PR-Vestige

The place to show off and tell us all about your XMs (or even other cars). Should it be a big project, or just some general pics, start your thread in here.
citroenxm
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Re: My Citroen XM 3.0 PR-Vestige

Post by citroenxm » Thu Jul 26, 2018 8:59 pm

Ive got two lots of rear quarters i removed from the two dervs that went 2 years ago and theres another pair still in the 24v shell...

Ive got yogs log book.. id ideally like to get that sorted so its not hanging around me for years to come..
1990 H reg V6 24v Manual .. in progress.. on SORN
Projects:
92 Bx Txd Turbo
92 L Xm 2.1t D auto project
Others
55 C5 V6 24v Auto toy
54 Xsara picasso 2.0 8v Hdi
Shit thats scarey.. Two XMs left...

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Dean
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Re: My Citroen XM 3.0 PR-Vestige

Post by Dean » Sun Jul 29, 2018 10:14 pm

Managed to solve the FDV pulsing and hissing constantly issue this weekend and it turns out that somebody left one of the ABS valve blocks bleed bolts undone when they last bled the brakes :roll:
I still have a problem with the steering assistance, when first started cold it pulses a bit for a second or two but then works fine, then 10 seconds after pulling off the drive i lose all assistance for a good two miles, its odd as the assistance always comes back at exactly the same place down the road every time, when starting again the same day assistance is there straight away, or if left sitting all day is not there from start-up but comes back within a few hundred yards of driving. This does sound to me like air ingress into the pump but i can find nothing wrong and the suspension goes up and down fine during the absence of power steering assistance with no pressure warning lights on.

The other issue is my tick times are down to 10 seconds but i will have to check the return pipes to see what can be seen there.

I still have not looked into the lack of soft mode and loss of sport mode dash light when operating the switch. The light comes on with the ignition but thats it, now the car holds hydraulic pressure when left i have found the hydractive valve does not activate when opening the doors, only when turning the ignition on, giving a jolt. When driving off the suspension remains in soft mode and then triggers firm after crossing the speed threshold which is where it stays, this behavour sounds like a sensor failure yet the suspension eCU has logged no faults.

I need to make time to look into this really :roll: :D .

D
92 Citroen XM Prestige 3.0i Auto R.P5678
14 Mitsubishi L200 Trojan
89 Talbot Express motorhome Auto-Trail coachbuilt (looking for bonnet, wings, scuttle panels etc)

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White Exec
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Re: My Citroen XM 3.0 PR-Vestige

Post by White Exec » Mon Jul 30, 2018 5:28 am

Might be that system is holding pressure, but not enough. Soft mode is kept locked in (at the suspension regulators) by system pressure being higher than centre sphere pressure. If it drops off, system will go firm.
Rapid clicks
- how good is the Acc sphere?
- maybe a system internal leakage, causing pressure to drop off . . . does use of steering or brakes affect the click rate while car is stationary?
Maybe do a check on the LHM return rate of the pipes at the octopus which might give a clue which bit of the system has excess leakage.
Annoying fault.
Chris
1996 XM 2.5TD Exclusive RP7165 Polar White
2003 RAV4 D4D 2.0 5dr LHD Silver WORKHORSE
1989 BX19RD Delage Red Deceased; 1998 ZX 1.9D Avantage auto Triton Green Company car 1998-2001; 2001 Xantia 1.8i auto Wicked Red Company car 2001-2003

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Dean
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Re: My Citroen XM 3.0 PR-Vestige

Post by Dean » Mon Jul 30, 2018 4:44 pm

Main pressure is fine as the regulator reaches cut out, i checked that recently and returned it to stock pressure during the belt slippage episode.

Acc sphere is new and good, i suspect leakage but not sure what from, the returns should shed some light on that.

The hydractive issue is an electrical one because when the car is turned off after a drive the suspension stays in firm with the hydractive valve vibrating very loudly through the car, opening the door does nothing but turning the ignition fully off and back on re-energises the valve and the car leaps up as the electrovalve opens for the first time since the journey began so that rules out a fluid pressure problem.

D
92 Citroen XM Prestige 3.0i Auto R.P5678
14 Mitsubishi L200 Trojan
89 Talbot Express motorhome Auto-Trail coachbuilt (looking for bonnet, wings, scuttle panels etc)

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Dean
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Re: My Citroen XM 3.0 PR-Vestige

Post by Dean » Mon Jul 30, 2018 8:16 pm

I have just checked and the hydractive ecu puts out a constant 11v to the solenoid valve, it either times out and outputs no voltage or around 11v and that is it.

I swapped this ecu out (the cars original) with another and that ECU triggers at 12v for 1-2sec and then switches to a holding voltage of about 6v so i have left this ECU in as that looks right.

No sport mode light on the dash still other than at ignition on.

Hydractive sport switch works fine

Throttle position switch works fine

Brake pressure switch works fine

I will continue again tomorrow.

D
92 Citroen XM Prestige 3.0i Auto R.P5678
14 Mitsubishi L200 Trojan
89 Talbot Express motorhome Auto-Trail coachbuilt (looking for bonnet, wings, scuttle panels etc)

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White Exec
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Re: My Citroen XM 3.0 PR-Vestige

Post by White Exec » Mon Jul 30, 2018 9:09 pm

Does look like susp ecu fault.
Should be 12v-ish for 0.5sec, then what looks like c.3v continuous.
Does it have the extra diode(s)?
Progress!
Chris
1996 XM 2.5TD Exclusive RP7165 Polar White
2003 RAV4 D4D 2.0 5dr LHD Silver WORKHORSE
1989 BX19RD Delage Red Deceased; 1998 ZX 1.9D Avantage auto Triton Green Company car 1998-2001; 2001 Xantia 1.8i auto Wicked Red Company car 2001-2003

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Dean
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Re: My Citroen XM 3.0 PR-Vestige

Post by Dean » Mon Jul 30, 2018 9:29 pm

Im not getting 3v continuous hold voltage, i'm getting 6v but that was better than a constant 11v regardless.
I am wondering if there is another issue that has caused ECU failure as i still have no Sport mode light.

Hydractive 1 does not have diode failure, not sure i have heard of it or driver failure, wouldn't know where the Diodes would be if it does have any?

D
92 Citroen XM Prestige 3.0i Auto R.P5678
14 Mitsubishi L200 Trojan
89 Talbot Express motorhome Auto-Trail coachbuilt (looking for bonnet, wings, scuttle panels etc)

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White Exec
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Posts: 4563
Joined: Fri Mar 11, 2011 7:38 pm
Orga / RP numbers: RP7165
1996 2.5TD saloon, manual, Polar White
Location: ex-Ealing, Cheshire, W.Sussex & Surrey. Now living in Sayalonga (Malaga, Spain)

Re: My Citroen XM 3.0 PR-Vestige

Post by White Exec » Tue Jul 31, 2018 6:11 am

Thought that H1 would have had an internal diode built into its EV, same as H2.
Do we know otherwise?
Either way, fitting an additional external one* would provide ecu protection, and ensure proper EV operation.

Although the 3v hold-in voltage is what the manual states, it's actually not that but a 12v square wave PCM run at around 25% duty, so it typically looks like 3v or so. If using a digital testmeter, these can deal with these waveforms differently, so it might be worth checking it with a good old-fashioned analogue meter, which averages the 1kHz pulsed waveform better.

* 400v 3A or 6A will be comfortably robust, stripe on diode to +ve.
Chris
1996 XM 2.5TD Exclusive RP7165 Polar White
2003 RAV4 D4D 2.0 5dr LHD Silver WORKHORSE
1989 BX19RD Delage Red Deceased; 1998 ZX 1.9D Avantage auto Triton Green Company car 1998-2001; 2001 Xantia 1.8i auto Wicked Red Company car 2001-2003

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Dean
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Re: My Citroen XM 3.0 PR-Vestige

Post by Dean » Tue Jul 31, 2018 10:04 am

I was using an analogue meter Chris, the needle was gently waving between 6-6.5v with the substitute ECU and pegged at 11v with the old one.

I took the car out this morning to try it and there is no difference, no sport light and hard suspension still so i have unplugged the ECU for the moment just incase there is something else wrong that could cause damage to it. It worked fine and then it didn't one day while out driving so i am confident it is not just something that is unplugged.

D
92 Citroen XM Prestige 3.0i Auto R.P5678
14 Mitsubishi L200 Trojan
89 Talbot Express motorhome Auto-Trail coachbuilt (looking for bonnet, wings, scuttle panels etc)

Addicted to Crackanory

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White Exec
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Orga / RP numbers: RP7165
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Location: ex-Ealing, Cheshire, W.Sussex & Surrey. Now living in Sayalonga (Malaga, Spain)

Re: My Citroen XM 3.0 PR-Vestige

Post by White Exec » Tue Jul 31, 2018 11:41 am

Have just pulled out the H1 manual pages.
H1 EV solenoid is stated as 3-5ohm resistance, and a running voltage of 5-6v.
So you look ok.

(At 13.5v, H2 EVs draw 3A for 0.5sec, then 0.5A hold-in (measuring c. 3v). DC res of these EVs is c. 4.8ohm.)
Chris
1996 XM 2.5TD Exclusive RP7165 Polar White
2003 RAV4 D4D 2.0 5dr LHD Silver WORKHORSE
1989 BX19RD Delage Red Deceased; 1998 ZX 1.9D Avantage auto Triton Green Company car 1998-2001; 2001 Xantia 1.8i auto Wicked Red Company car 2001-2003

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