C5 x7 suspension

[David S]

Was reading the last comment about the front being very low, but you are probably correct Armidillo that both ends are not rising. Odd, if the pump runs OK and has plenty of LDS, it may be an internal fault and the level adjustment operations may have been disabled.
Any fault codes known?
In addition to that 40A fusible link, which is also in the 2.7HDi, there is a control relay that can fail. If the pump motor runs normally, those should be OK. Loss of prime might explain it.

 

[ben stellini]

Can we assume that the car starts OK - which would prove that the battery is in good shape?

Car starts fine

 

[ben stellini]

Was reading the last comment about the front being very low, but you are probably correct Armidillo that both ends are not rising. Odd, if the pump runs OK and has plenty of LDS, it may be an internal fault and the level adjustment operations may have been disabled.
Any fault codes known?
In addition to that 40A fusible link, which is also in the 2.7HDi, there is a control relay that can fail. If the pump motor runs normally, those should be OK. Loss of prime might explain it.

The pump doesn’t make any noise , only when the raise button is used

 

[ben stellini]

See post #1:

"Hi the hydroneumatic suspension 2008 2.7L x7 has stopped working " - so it's a V6.

Wonder if the daughter realises how lucky she is (apart from current problems)?

She really likes the car for long distance travel

 

[ben stellini]

Curious about the button making a noise. Are you perhaps saying that you've selected the suspension "High" setting? Do you mean the actual button makes a noise, or that you can hear a hum or buzz from somewhere in the car when you press said button? Has the noise changed, or has it always been a "feature" of the car?

If you are saying the button triggers a noise from somewhere in the car, then it might indicate that the pump is still working, in which case perhaps you have a fluid shortage? You say there are no (obvious) leaks, but have you actually checked the fluid level? A design flaw in Xantias allowed fluid to leak into the driver's footwell - there were no visible leaks, but the level in the reservoir would drop. Eventually you would realise the soles of your shoes were oily...

Looked around the car for leaks , none found, topped up the resouvoir with a litre of correct fluid , no difference

 

[ben stellini]

Ask her or a helper to listen foir the pump motor, in the front of the hydralic unit under the bonnet. It should start to lift the car. It isn't noisy, but should be detectable. If it doesn't start up, fuses are the next check. The control fuse is at the glove box fuses, but the main motor maxi-fuse is hard to get at, It's between the battery and the mud guard in a small housing (possibly red) and will need the battery removed for normal sized fingers. Perhaps a job for a dealer or auto electrician.

With battery disconnection don't forget to wait after disconnection before touching anything (including the doors) and do the same wait at reconnection. This is to keep the computers happy - they need time to shut and to reboot..

If the maxi fuse has blown, an electrician would be your best bet for just a replacement, though removal of the pump will need an LDS top up. You can read about the problem I am guessing about at

Citroen C5 Suspension Pump Reconditioning

Motor winding in the suspension pump (BHI) The introduction of Hydractive 3 to Citroen (with the first generation C5) brought about a radical change in the established hydraulic orthodoxy of past C…

elisdavies.home.blog

Thanks for the info

 

[ben stellini]

So the pump motor can turn. I was hoping it was an easy fuse fix.

I'm sorry about locating the battery up front - that's the common location for four cylinder engines.

That’s ok no problem, I knew what you meant

 

[Armidillo]

...
Any fault codes known?
In addition to that 40A fusible link, which is also in the 2.7HDi, there is a control relay that can fail. If the pump motor runs normally, those should be OK. Loss of prime might explain it.

Ben has stated in an early post that no OBD codes come up. They have had the NRMA out for a look, so presume they read codes. An elderly friend recently called the NRMA when his 307 HDi wouldn't start - only code was a glow plug fault, which NRMA guy declared to be the problem (turned out to be a key issue) - so they do read codes.

BTW, it is a 2.7 HDi...

 

[GreenBlood]

If the car needed 1L of LDS should we consider a ruptured sphere? I know when these late saucer spheres fail they do so in a big way?
Just putting it in the mix of possibilities. . .

 

[Ken W]

A lot of the cheaper code readers will only read engine codes. They cannot make sense of suspension, gearbox or other particular PSA ECUs.

Who else in Armidale could help. Is there some Peugeot expertise in town? Any suggestions Armidillo?

Cheers, Ken

 

[ben stellini]

If the car needed 1L of LDS should we consider a ruptured sphere? I know when these late saucer spheres fail they do so in a big way?
Just putting it in the mix of possibilities. . .

Hi the hydroneumatic suspension 2008 2.7L x7 has stopped working , and is so low you can’t drive it fluid is ok no leaks . Nothing comes up in dash to display a fault . button on the console makes a noise nothing happens though . Where to start looking fuse ? Reset BMI , faulty pump. Thanks

Update on the suspension, my daughter drove the car around the car park at uni . Made no difference, so I said drive it home 2 km away , after 500m down the road the suspension started working to the normal height ,Iam happy it is drivable though still none the wiser .

 

[seasink]

An air lock?

 

[Ken W]

Sounds like the pump eventually primed itself. I would say it probably needs more LDS added to the reservoir though and I think to do that properly is a Diagbox exercise. Anyone know a shortcut process?

Maybe put the suspension on low, then fill up the LDS reservoir until the LDS just covers the strainer under the lid???

Cheers, Ken

 

[David S]

Suspension on low and fill to about the seam in the reservoir works. The gauge in the tank is for use when you use DiagBox.
The question is why did it need the LDS added? If it's really not leaking (there are a few places where leaks are not that obvious), it must have ruptured one or more spheres. Don't keep diving it like that. Does it feel bouncy or is one corner or end hard?
.. and loosen the cap if going to full height and then down again so the tank doesn't bloat as the LDS returns to the reservoir.

 

[fritzelhund]

Sounds like the pump eventually primed itself. I would say it probably needs more LDS added to the reservoir though and I think to do that properly is a Diagbox exercise. Anyone know a shortcut process?

Maybe put the suspension on low, then fill up the LDS reservoir until the LDS just covers the strainer under the lid???

Cheers, Ken

I suspect Ken, you are on the money .. again.

My ( non X7 ) C5 did a similar thing after the front hydractive stiffness sphere ( the centre one ) ruptured after a vigorous approach to a car park speed bump. The symptoms were as described .. no pump action, drove home on suspension stops then a SELF recovery .. in short a system full of nitrogen where it shouldn't have been.
David S above also offers good advice ( as usual ) .. but sensing the suspension spheres at all 4 corners won't give a clue about the stiffness sphere states unless the driver is familiar with the "feel" of the car when it is IN and NOT in sport mode.
My old C5 does not have great difference in road feel between the two modes .. a non sympathetic or sensitive driver may not even feel ANY difference.
The front stiffness spheres are difficult to access and suffer a hotter working environment than the suspension spheres making them more likely to rupture in old age. The LDS level being low ( without any obvious leakage elsewhere ) would indicate the golden liquid has gone into a ruptured sphere .. and IIRC should be about 380 millilitres, the volume of a saucer sphere .. ie a bit more than a third of a litre.

 

[ben stellini]

Suspension on low and fill to about the seam in the reservoir works. The gauge in the tank is for use when you use DiagBox.
The question is why did it need the LDS added? If it's really not leaking (there are a few places where leaks are not that obvious), it must have ruptured one or more spheres. Don't keep diving it like that. Does it feel bouncy or is one corner or end hard?
.. and loosen the cap if going to full height and then down again so the tank doesn't bloat as the LDS returns to the reservoir.

Hi David Iam not with my daughter and she couldn’t see any leaks , we put in 500mls , trying small things to see what would work. I will check your advice on the c5 with the resouvoir. The car drives and feels normal.

 

[David S]

This may help you Ben ...

In addition to a sphere at each corner, a Hydractive 3+ car has a valve block at each end known as a 'stiffness regulator' with a sphere on it. X7 has two spheres on this unit at the rear. If the suspension feels hard at one corner, then it could be a flat sphere. You have to remove them to test them properly, but if you have no way of pressure testing them, swapping the two sides and seeing if the 'hardness' moves could be a workaround. They generally last very well until they don't, so good used is not a bad option.

Manually depressurising the suspension to remove a sphere:
Front and rear can be depressurized separately. Dispose of any expelled LDS.
Disconnect the battery, support the vehicle on axle stands (or hoist), wheels hanging and use the bleed nipples with a hose fitted. Front bleed nipple on top of the RH strut. Rear axle has a bleed nipple on stiffness regulator block per image below.

X7 data for testing 'saucer' slimline spheres:
Volume 385cc. Pressure tolerances : < 50 Bar = +/- 2.5 Bar / >= 50 Bar = +/- 4%; +/- 0.5 Bar
Sphere markings as XXNN = XX damper type and NN Bar static pressure.
Front: All except DW12 MC50, DW12 MB45
Rear: Sedan ME40 Estate LS50
Front Stiffness Reg: All except DW12 KR70, DW12 LX75
Rear Stiffness Ref: Sedan GV44 Estate MA52
Tighten to 2.7 daNm = 27Nm. However, fitting spheres is normally just like fitting an oil filter - tighten until the seal touches and then maybe a 1/3rd to 1/2 hand turn is usually enough for it not to leak.

 

[jonhardy]

Getting back to C5's being stuck on "high" we've had two problems both a few years ago.
Years ago the C5 Hdi facelift wagon came up with "suspension fault" Christmas Eve just before Son and others were about to head from Adelaide to Tasmania for a cycling trip. (Why didn't they just ride to Melbourne I asked). They went in the C5 series one 8v hdi hatch instead, leaving a fair bit of stuff behind.
I didn't have an OBD reader in those days so up on stands and underneath after checking everything I could see from above. Eventually it turned out to be a broken retention clip on the plug to the solenoid controlling the sphere on the sub-frame, kind of below the turbo. Fixed with a figure 8 cable-tie. Stays fixed too.
And we had to assume it had been broken by the dealership as they'd had the subframe off some time before, but why, I cant remember. Ah yes, blocked particle filter, under warranty.
Some time before that there had been a steering rattle : "might be the rack" they said with a serious sad look.
No, they'd left the sway bar drop links faintly loose! Probably couldn't find the right Torx.

Another time, after a blowout caused by serious rear tyre wear on the inside of the tread (trailing arm bearings), the spare was installed using the time honoured method of set suspension on high and use the jack as a prop. All good.
Onlooking young passengers impressed with Son's strange car. Except it refused to lower even while limping in to Swan Hill from Pink Lake.
So poor Dad has to set off from Adelaide with a load of bits, including an electric regulator carefully removed from a resting V6 Petrol Series One.
Working on a huge area of flat bitumen by the sale yards where all the cattle trucks park on sale day, I carefully swapped the regulator, with the battery disconnected, and eventually after a few tries it all came good. Back home, I swapped the item back and it made no difference. Remains a mystery.

 

[ben stellini]

Getting back to C5's being stuck on "high" we've had two problems both a few years ago.
Years ago the C5 Hdi facelift wagon came up with "suspension fault" Christmas Eve just before Son and others were about to head from Adelaide to Tasmania for a cycling trip. (Why didn't they just ride to Melbourne I asked). They went in the C5 series one 8v hdi hatch instead, leaving a fair bit of stuff behind.
I didn't have an OBD reader in those days so up on stands and underneath after checking everything I could see from above. Eventually it turned out to be a broken retention clip on the plug to the solenoid controlling the sphere on the sub-frame, kind of below the turbo. Fixed with a figure 8 cable-tie. Stays fixed too.
And we had to assume it had been broken by the dealership as they'd had the subframe off some time before, but why, I cant remember. Ah yes, blocked particle filter, under warranty.
Some time before that there had been a steering rattle : "might be the rack" they said with a serious sad look.
No, they'd left the sway bar drop links faintly loose! Probably couldn't find the right Torx.

Another time, after a blowout caused by serious rear tyre wear on the inside of the tread (trailing arm bearings), the spare was installed using the time honoured method of set suspension on high and use the jack as a prop. All good.
Onlooking young passengers impressed with Son's strange car. Except it refused to lower even while limping in to Swan Hill from Pink Lake.
So poor Dad has to set off from Adelaide with a load of bits, including an electric regulator carefully removed from a resting V6 Petrol Series One.
Working on a huge area of flat bitumen by the sale yards where all the cattle trucks park on sale day, I carefully swapped the regulator, with the battery disconnected, and eventually after a few tries it all came good. Back home, I swapped the item back and it made no difference. Remains a mystery.

Thanks for the info on depressurisation of the system, the cars are certainly quirky to say the least . Not sure how to test the spheres , the rear is soft and feels ok the front is hard and crashes hard over bumps . I was going to start with the centre sphere at the front first , and see if it makes a difference. The steering firstly there are no noises . on acceleration the car pulls to the right, on de acceleration it pulls to the left just for a moment , feels weird and unnerving . I suspect worn steering part or engine mount going to a look on a hoist this weekend, I don’t think the 2 problems are related .

 

[David S]

Get an assistant to move the car a few feet back and forward and see if the wheel moves about fore/aft in the wheelarch. That normally tells you the rear lower control arm bush has failed. It is common. The other common front end fault is the bush in the bottom of the front uprights. Look for bits of rubber being extrduded ot the metal shell having been displaced. There is also a pivot in the bottom of the front knuckle that will eventually start to bind, so ensure you can turn each wheel left and right freely when lifted off the ground.