2007 c5 suspension

This is the Forum for all your Citroen Technical Questions, Problems or Advice.

Moderator: RichardW

citroen7
Posts: 151
Joined: 09 Jun 2006, 10:29
x 1

2007 c5 suspension

Post by citroen7 »

i have just bought a c5 2.2 with hydractive suspension with a small fault in that the front suspension drops down quite quickly at rest and overnight the whole car drops down. it pumps up ok and drives very nicely but even with the engine running at idle it sinks and the pump cuts in and up she goes,i am assuming i have a leaky front strut or the front acc sphere has gone duff.Has anyone got a proceedure for diagnosing the stuts or do i just go for the sphere it certainly reminds me of my bx days when a duff acc sphere was a sympton of the pump cutting constantly,any thoughts?

User avatar
GiveMeABreak
Forum Admin Team
Posts: 21216
Joined: 15 Sep 2015, 19:38
x 2115

Re: 2007 c5 suspension

Post by GiveMeABreak »

Your issue may also be inside the Hydro-electric Interface (BHI) itself - where there are 2 anti-sink valves. So in the absence of any leaks elsewhere, this may be a consideration.

citroen7
Posts: 151
Joined: 09 Jun 2006, 10:29
x 1

Re: 2007 c5 suspension

Post by citroen7 »

is there anyway to test this?

User avatar
GiveMeABreak
Forum Admin Team
Posts: 21216
Joined: 15 Sep 2015, 19:38
x 2115

Re: 2007 c5 suspension

Post by GiveMeABreak »

I know Diagbox can test some of the electrovalves - but I can't recall whether the anti sink ones are included from memory - and of course you will be using Lexia; but go into the suspension ECU after you perform a global test, (the ECU should be called SUSP_ECOTEC or similar), then select the appropriate test parameters and see if you can find the anti sing electrovalves there. If not, try a customised parameters and see if you can select them from there.

citroen7
Posts: 151
Joined: 09 Jun 2006, 10:29
x 1

Re: 2007 c5 suspension

Post by citroen7 »

well i bought a lxia for the xantia and never used it ! will it do the c5 or do i need to buy different software? also is there any reason not to drive it would only be short journeys and thanks for your input.

User avatar
GiveMeABreak
Forum Admin Team
Posts: 21216
Joined: 15 Sep 2015, 19:38
x 2115

Re: 2007 c5 suspension

Post by GiveMeABreak »

The C5 uses CAN wiring, but as you haven’t mentioned what version of Diagbox you are using I can’t say, but I suspect you may be using a stand alone version of Lexia.

Your interface may also need updating, but all you can do is try- no harm it that. The C5 and C5 MkII use Lexia anyway, but probably needs to cover models up to 2006 / 2007 I should imagine to ensure best chances.

citroen7
Posts: 151
Joined: 09 Jun 2006, 10:29
x 1

Re: 2007 c5 suspension

Post by citroen7 »

the lexia i bought is to download onto a laptop but the laptop i had because of the way it came to me i couldnt get past admin to download it .I have a new one now so will dig it all out of the cupboard,if you see a post about computers and lexcia you will know i have ballsed it up!

User avatar
GiveMeABreak
Forum Admin Team
Posts: 21216
Joined: 15 Sep 2015, 19:38
x 2115

Re: 2007 c5 suspension

Post by GiveMeABreak »

Ok, so post any issues with that in the Diagnostics section - and look there to see if you can find any help first.

User avatar
GiveMeABreak
Forum Admin Team
Posts: 21216
Joined: 15 Sep 2015, 19:38
x 2115

Re: 2007 c5 suspension

Post by GiveMeABreak »

As for driving it around, I can't say at this point whether the anti sink electrovalves also play a part in maintaining a certain height or whether these are independent form the inlet and exhaust electrovalves. I'll have to see if I can find any detailed information.

citroen7
Posts: 151
Joined: 09 Jun 2006, 10:29
x 1

Re: 2007 c5 suspension

Post by citroen7 »

i forgot to mention i did an experiment this morning and put the car up to high and left it i have just checked it and the back has stayed up but the front has sunk right downso would it be safe to assume there is nothing wrong with the rear end?and another thought if one front strut was leaking would that cause the whole front to sink?

User avatar
GiveMeABreak
Forum Admin Team
Posts: 21216
Joined: 15 Sep 2015, 19:38
x 2115

Re: 2007 c5 suspension

Post by GiveMeABreak »

The front and rear axles are supplied separately.

So your problem would indeed appear to be at the front - again either the front electrovalves or front anti sink. If you had a strut leak, it should be plainly obvious from looking at the strut tops inside the wheel arch o or around the LDS return pipes. These return pipes can split or get nicked - and are low pressure - just returning the excess fluid back to the tank. You may need to take the wheel arch off to properly see.

citroen7
Posts: 151
Joined: 09 Jun 2006, 10:29
x 1

Re: 2007 c5 suspension

Post by citroen7 »

well this is still no further forward so today after charging the battery and draging into the garage and on to the ramp i made a start. the suspension at this point would not go up at all so i put 2 ltrs of fluid into the resovoir and following some advice from the facebook page (thanks again Paul) i got the suspension to go up to start with the front struggled to stay up but settled down prety much back to how it was,with the engine running the front drops slowly and the pump kicks in to adjust it and it left switched off the front sinks right down. 2 things i have noticed ,the passenger side strut is wet inside the gaiter and there is some evidence of lds in the wheel arch under the resovoir but no major leak. I was wondering would the passenger side strut passing fluid back quickly cause this ? also would the center sphere have any bearing on this problem ant advice or pointers would be most welcome!

User avatar
GiveMeABreak
Forum Admin Team
Posts: 21216
Joined: 15 Sep 2015, 19:38
x 2115

Re: 2007 c5 suspension

Post by GiveMeABreak »

Just on the LDS and fluid issue....

LDS tank bursting / splitting can be caused when the car has been raised off the ground with the wheels hanging and then dropped back to the ground again without following the correct procedure - namely:

Before raising the vehicle where the wheels will not be supported, the suspension should be raised to the highest position and the LDS cap removed. Then later when work has been completed (especially tyre fitters!), the car should be lowered, then the suspension returned to normal position and the LDS cap replaced. Failure to do so can cause uncontrolled LDS fluid to be forced back into the tank under the weight of the car and this can burst the tank. If not burst, fluid can leak out as the vent cap hole is insufficient for the pressure and LDS can then seep out under ontot he BHI and pump. Fluid can get into the seams of the motorised pump and mix with carbon from bushes and overheating, shorts will occur.

All here, which is why we created some labels:

viewtopic.php?t=62058

citroen7
Posts: 151
Joined: 09 Jun 2006, 10:29
x 1

Re: 2007 c5 suspension

Post by citroen7 »

i was aware of most of that next time i visit the mot center should be fun,because they wont do that and probably wont let me either but that is going to be next year now,i have just been out and cleaned the bhi and the pumpi will do some "arobics" with the suspension tomorrow and see if any has leaked outi must admitt i was suprised to use 2 litersthat stuff is not cheap!

User avatar
GiveMeABreak
Forum Admin Team
Posts: 21216
Joined: 15 Sep 2015, 19:38
x 2115

Re: 2007 c5 suspension

Post by GiveMeABreak »

If you've had to put that much in - you obviously have a bad leak.

Re the MOT, only needs all that doing that I described if the wheels are left hanging - the MOT shouldn't require that - mine use a four post lift with the wheels supported - not hanging.