Citroen C5 MK I 3.0 Suspension Depressurisation

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cornesoutafrica
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Citroen C5 MK I 3.0 Suspension Depressurisation

Post by cornesoutafrica »

Hi Marc.

I got it sorted. I switched on the function to activate or deactivate the auto headlights on the central display. Biggest mistake ever. Switched the function off and all was well. Diagnostic is also put away now... till I need it to depressurise my c5 suspension to change the spheres which has just arrived.

I cant seem to log into the suspension part of the diagnostic with the psa-com. So can’t depressurise the system. But will worry about that later.. for now I am good again. Phew

Regards
Corne
Hi Marc

Thanks. I will try again but if I have to do it manually. Should I put car in low position. Disconnect the battery? Then open bleed nipple? Will there be any issues once I have it all back and start het and switch back to normal height? Will the pump prime? I do have LDS to top up.

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GiveMeABreak
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Re: Weird autoheadlight behaviour Citroën C4

Post by GiveMeABreak »

Ok, thanks for letting me know - that has saved a trawl!

You shouldn't have a problem depressurising using the diagnostic - and if all else fails you can manually depressurise the front and rear axles independently if need be using the valves.

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GiveMeABreak
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Re: Weird autoheadlight behaviour Citroën C4

Post by GiveMeABreak »

Can I ask why you need to depressurise the system? Is there a specific job you are doing?

You will need to raise car to highest setting, remove LDS tank cap, support the car safely on axle stands at the jacking points (don’t use the subframe).

Then you can lower the suspension to the lowest setting, lower driver window and ensure bonnet is raised.

Close all doors and leave the car for 5 minutes without opening doors or pressing switches to allow car ECUs to memorise settings and go to sleep mode.

Then disconnect battery negative and ensure it cannot reconnect accidentally.

Then you can depressurise the axle(s) you need to work on depending on what you want to do. Discard any LDS fluid that may come out and don’t reuse,

When finished you will need to tighten bleed valves, top up the LDS reservoir to between the min and max marks as shown on the outer tanks markings:
C5 MK I LDS Tank Level.PNG
C5 MK I LDS Tank Level.PNG (39.06 KiB) Viewed 217 times
The system may well need to be primed by applying some pressure into the reservoir. Again ensure all doors are shut and reconnect the battery. The pump may try to engage.

Leave the car for a few minutes to allow the BSI and ECUs to wake up and initialise without opening any doors.

After a few minutes you can start the car and put the suspension back to normal first of all. It may take some time to raise the car. If it does, you won’t have to apply pressure. Then you can raise it right up to max and allow the car to stabilise at the highest setting.

Remove your axle stands and proceed to bleeding the circuit.

From highest position, lower car to lowest position. With engine still running, SLOWLY turn from lock to lock 10 times and do not hold the steering on the full lock either way, return steering to ahead position

After this, top up LDS to between min and max levels if necessary and watch for any bubbling. If there is bubbling, allow the bubbles to disappear the repeat the raising, lowering of suspension one more time and do the lock to lock another 5 times slowly. Repeat checks for bubbles and repeat until there are none.

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GiveMeABreak
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Re: Citroen C5 MK I 3.0 Suspension Depressurisation

Post by GiveMeABreak »

Corne - topic split to keep the issues separate.

It might be an idea to post your VIN for the C5 here in case you need additional info later.

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Re: Citroen C5 MK I 3.0 Suspension Depressurisation

Post by cornesoutafrica »

Hi Marc

The reason I want to depressurise the system is because I want to change the rear suspension piston covers and change the original spheres, I think after 17 years they might aswell be renewed.
I will first try again with my diagnostic tool but if it fails then I will have to go this way.
I must admit. The LDS is seriously expensive this side of the world.

Will keep jou guys updated with pictures.
Regards
Corne

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GiveMeABreak
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Re: Citroen C5 MK I 3.0 Suspension Depressurisation

Post by GiveMeABreak »

Ok, lower car to lowest suspension setting and then if you are using Lexia, run a Global Test on all the ECUs, when it has finished, move onto the 'Suspension' item in the list, then select. then choose 'Eco Suspension Ecotech', and select, then validate, then from the menu, go to the bottom of the list and is should have a section saying 'Depressurise'. Select that and follow instructions.

Apologies if you have already got this far :-D I'm not sure what issue you are having with the diagnostic tool, but that should be the process above.

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Re: Citroen C5 MK I 3.0 Suspension Depressurisation

Post by cornesoutafrica »

Thanks Marc


Will try it now. I have a PSA com diagnostic but it is kind of the same. Let me put car in lowest position first and do what you told me. I saw the eco tech suspension link. Will give it a try

Thanks

Corne

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GiveMeABreak
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Re: Citroen C5 MK I 3.0 Suspension Depressurisation

Post by GiveMeABreak »

That is the suspension ECU on this model and that is where you can depressurise from hopefully the PSA-COM unit will be able to do it - but I know it's a cut down version of the full-blown Doagbox software so may not have all the functions.

cornesoutafrica
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Re: Citroen C5 MK I 3.0 Suspension Depressurisation

Post by cornesoutafrica »

Its definitely a cutdown version from diagbox. But I gave up trying to install it. Did all the steps as per video supplied but the unit blinks twice and thats it. Computer doesn’t even pick it up. So I gave up and got psa-com.
It shows the ecu. But doesn’t connect. Haven’t put car in low position beforehand. The car is not with me it is in storage. So will try tomorrow. Its my mission to get it to work.
I think there might be a difference in ridequality?

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GiveMeABreak
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Re: Citroen C5 MK I 3.0 Suspension Depressurisation

Post by GiveMeABreak »

Never ride with it in the lowest setting - that's for service operations and to assist with hitching a towbar.

I know Diagbox is a pain to install.

You have to make sure you disable any antivirus, run everything as an administrator, and ensure Windows update service is stopped, plus allow all firewall requests through. The you have to plug the USB cable into each port on the laptop and allow the driver to install, then go onto the next one etc.

cornesoutafrica
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Re: Citroen C5 MK I 3.0 Suspension Depressurisation

Post by cornesoutafrica »

Hi Marc

I won’t drive the car in low. Ever. Lowrider is not my thing anyway ha ha. Im used to hydraulic Citroens. (I have 3 DS’s)
Will try your suggestions. I have to get the diagbox up and running properly. The PSA com is not bad. It does what it says, only not the suspension...
Atleast its almost weekend which gives me ample time to figure it out.
Must say I missed fidling around with modern Citroens. Its great being at it again.

Cheers
Corne

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myglaren
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Re: Citroen C5 MK I 3.0 Suspension Depressurisation

Post by myglaren »

If it is like mine you can't anyway.
I've inadvertently left mine in low and driven off - it rises to normal height within a few seconds.