C5 2005 Hydro 3 - Front dropping way to fast

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EssoUnknown
Posts: 8
Joined: 19 Jun 2020, 21:22

C5 2005 Hydro 3 - Front dropping way to fast

Unread post by EssoUnknown »

Hello ppl, im new here and i have a problem with Hydraulic suspension
My car is Citroen C5 2005 2,2HDI with Hydroactive 3

Today i raised the car to the top 2nd position and removed the front brake calipers because handbrake on left side was not holding at all, it was tested at 0.
The right handbrake hold good....

So after i removed the brake calipers i pressed down to lower the car from 2nd level and the front just dropped down 2 levels to normal position and then raised again to 1st level, it fall down way to fast and it scared me.
i noticed that today to before taking the front brake calipers off, it was on 1st height level and i pressed down to get to normal and front end just droped, not lowering normaly as before it just dropped fast.

so my question is:
Do hydroactive suspension use same oil for brakes and hydraulics? and does it droped because the caliper was removed and brake fluid line was just taped so fluid cant escape?
or is something else broken ?

I tend to fix car by my self so going to dealers is not an option

ty in advanced

Hell Razor5543
NOT Alistair or Simon
Posts: 10367
Joined: 01 Apr 2012, 09:47
x 952

Re: C5 2005 Hydro 3 - Front dropping way to fast

Unread post by Hell Razor5543 »

On the C5 the brakes are not (unlike previous green blooded Citroens) connected in any way to the hydropneumatics system. The suspension and the steering are (slightly) connected. It is likely your C5 uses DOT4 brake fluid (but somebody with more knowledge than I should be able to confirm/correct this).

EssoUnknown
Posts: 8
Joined: 19 Jun 2020, 21:22

Re: C5 2005 Hydro 3 - Front dropping way to fast

Unread post by EssoUnknown »

Ty 4 reply...

So that means its not because i removed calipers...

could it be that it drops fast because i started car and immediately pressed down button before waiting a minute for hydro pump to build up pressure or something?

Gibbo2286
Donor 2020
Posts: 4493
Joined: 08 Jun 2011, 18:04
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Re: C5 2005 Hydro 3 - Front dropping way to fast

Unread post by Gibbo2286 »

It's more likely that there's a problem with the front height corrector having got the wet in and corroded the contacts or maybe just the connector pins corroded.

EssoUnknown
Posts: 8
Joined: 19 Jun 2020, 21:22

Re: C5 2005 Hydro 3 - Front dropping way to fast

Unread post by EssoUnknown »

Ty Gibbo will check, it happen today to, car was on top 2nd position and it was standing like that for maybe an hour.
when lowering it to 1st position the back is going down smooth but the front dropped but this time left side first then right side,
another down position from 1st to normal went smooth on back and front, like its only problem when going from 2nd to 1st position, 1st to normal is ok

Could car loose pressure while standing on full height for longer period of time with engine off ( like 1h ) ??

I will do a LDS lvl check today while car is lowered all the way down...

Gibbo2286
Donor 2020
Posts: 4493
Joined: 08 Jun 2011, 18:04
x 724

Re: C5 2005 Hydro 3 - Front dropping way to fast

Unread post by Gibbo2286 »

It's pretty shocking when you have it at full height, dab the down button and it seems to hang for a while then drops like a stone with a crash onto the bottom bump stops, I had that happen when my front height corrector failed.

EssoUnknown
Posts: 8
Joined: 19 Jun 2020, 21:22

Re: C5 2005 Hydro 3 - Front dropping way to fast

Unread post by EssoUnknown »

I was returned from MOT coz front left handbrake was tested at 0 holding the brake while right was ok...
I fix it by removing caliper and working the handbrake mechanism first by hammer and wood, then by big screwdriver and finally with hand until inner spring was releasing by it self, it was stuck
open due to never ever using handbrake as its Automatic...

While i was working on that i kept the car at max height for longer period of time with engine off and every time it would drop after trying to lower it....
Today i finally fixed the brake so i did a test on Hydro

I can raise it to max and lower it to low without any issue ( did a 5-6 max-low tests ) if i dont hold it at max position for long, looks like it only happen when car stand on max for some time with engine off...
Not sure if that is normal ....

But i did check the LDS fluid in reservoir and i didnt like the color of it, it was kinda yellowish...

Is there some special way of flushing the LDS or i can just connect the return line to empty canister put car on max up and lower it max down so it drain all fluid to canister and then just top up new LDS ??

EssoUnknown
Posts: 8
Joined: 19 Jun 2020, 21:22

Re: C5 2005 Hydro 3 - Front dropping way to fast

Unread post by EssoUnknown »

and yes Gibbo it is scary to see it drop down faster then excepted, but mine newer hit the metal, its kinda like there is no enough fluid in front suspension it drop at first then lower normal to end
now it work as intended ill just skip part when i hold it up longer, maybe fluid flush will help there to...

I rule out sensors as car is 180tkm and in excelent condition, 0% rust under it, here in Croatia the weather is good so no heavy rains or big minuses when winter
i can of course be wrong....

wheeler
Posts: 4101
Joined: 21 Sep 2002, 19:07
x 130

Re: C5 2005 Hydro 3 - Front dropping way to fast

Unread post by wheeler »

Any fault codes in the suspension ECU?
The height sensors can fail with wear & tear not just corrosion.
The front & rear height sensors are the same part, you could always swap them front to rear to see if the fault changes.
Take good pics before removing them so you have reference to correct orientation.

EssoUnknown
Posts: 8
Joined: 19 Jun 2020, 21:22

Re: C5 2005 Hydro 3 - Front dropping way to fast

Unread post by EssoUnknown »

No codes, no faults, work as intended now
I just must not hold him for long on max position with engine off...

I tested sensors front and back by sitting on the each side and it automatically level car position