C5 II Hydractive 3 non sport sinking rear

[careca]

Hi, i searched quite a bit for this issue and found some things, but still it was not conclusive, so let's start from the start:
One day i parked my C5 II, and when i came back to it after some hours, the rear had dropped to a position even lower than if i used the buttons to put it in the lowest setting.
What makes sense to me is that what must be a valve that retains the oil is leaking internally, since i don't see anything on the floor, any marks of oil drops or anything, and i have read about a certain valve that can cause this, my problem is that no one ever explained where the valve is exactly.
So i assume there are 2 valves one for front, one for rear, if the valve closes while the pump is running the car raises, if the valves open the car drops, if the valves leak internally while the pump is stopped, the car drops. So if this is the case, what makes sense in terms of fixing? Honestly i kinda don't mind that it drops like this, but it's anoying that the front stays up, if anything i would like that the front drops too! XD

Thanks in advance.

[GiveMeABreak]

Pop your VIN up so I can see which system you have. Only the hydractive 3+ systems have a rear hydraulic block, and these systems are generally on the 2.2 models and up.

If this is the case and you don't have Hydrtactive 3+, then it may be:

1) The rear height corrector starting to play up
2) The BHI itself, specifically the rear anti-sink valve or
3) The rear outlet valve that permits lowering the vehicle

[careca]

Hi, thanks for the reply.
The vin: VF7**************[VIN obfuscated, can be read by forum staff]
I think i read a post where they mentioned that the hydractive 3+ has a sport button, mine doesn't, so i assume it's the normal, non plus.
I also read something about the height correctors, but it doesn't make sense to me that it could be that, since, for one all positions work fine, and once i unlock the car it goes to where it's supposed to.
Is there a single anti sink valve for both rear struts, or is it one for each wheel?
I am very interested in that 3rd option, it makes sense and it's most likely easier to swap than one in the pump, maybe.

[GiveMeABreak]

No all of the valves I mentioned above are contained in the BHI itself, so would need completely stripping down to get to the internal valves, although officially it states it can't be taken apart.

The BHI contains on this model:

The BHI, a monoblock which cannot be taken apart, is composed of the following components:

• An electric motor to drive the hydraulic pump
• A hydraulic pump with 5 axial pistons
• An anti-pulse accumulator, flow regulator
• 4 electrovalves: 2 per axle, 1 for inlet (raising the vehicle), 1 for outlet (lowering the vehicle)
• An electronic suspension ECU
• 2 anti-sink valves
• 6 hydraulic fluid filters: upstream and downstream of the electrovalves
• 1 overpressure valve

[careca]

Hi, that is very detailed, thank you.
It also seems like the only option is to replace to pump, sounds expensive. Because there aren't any spares for the internal parts, i assume.

[Hell Razor5543]

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