C5 X7 rear suspension fun.

[ActivaV6uk]

Dog bone connector already in hand but I've not been well enough to fit it yet.

So my C5 tourer has a nice habit of dropping the rear suspension to the floor making the bottom of the car actually drag on the ground and the suspension hit the bump stops. This isn't happening all the time but this is what I have found...

Bringing the car to mid/high (25 mph or less) , and then back down to normal on start brigs the suspension to height to normal and so long as the car isn't driven hard it will stay there for at least an hour. Not doing so can bring the back down randomly.

Hard cornering (360 degree 1/4 cloverleaf at 40mph) brings the suspension down to its stops at the back.

Hard acceleration (sports on auto box ,15 secconds hard gas down) makes the back fall but not all the way down just very low.

It takes 15-30 secconds to go from low to high mid, low to normal leaves the back down, and to get to low (registered on dash) the car has to be set to low and then left over night.

Citrobics generally the back comes up first then the front. The car lowers front and back smoothly and quickly front and back simultaneously from high/mid to normal in 2-3 secconds. No fluid loss of any type anywhere.

So sticking dog bone connector?

Andy

[GiveMeABreak]

Andy - you have the V6, and unlike the 4 cylinder versions, you have 4 height correctors - one on each wheel in common with the C6 (although the AMVAR function is not available). You also have a separate suspension ECU different from the BHI-integrated one on the 4 cylinder engines. So these are a different setup to the 4 cylinders and don't have the height correctors on the rear and front 'axles'.

I had a similar issue with the rear bottoming out on a steep dip so start with - which is shouldn't do, and later the suspension faulty warning came on occasionally, but ultimately the warning stayed off, and I had an issue where my directional lighting deactivated the directional function, and the suspension would not lower or raise on an intermittent basis. Had it checked at the dealer as it was under extended warranty and in my case I had both height correctors replaced - problem solved. Having said that though, mine never dropped out like you describe.

So I'm now wondering whether this is something else, but can't be sure without Diagbox to check the system.

[ActivaV6uk]

An update. I'm busy trying to get the diagnosis box software installed and working (it has issues ATM). However today the car pulled a new one on me.

The car drops the back more often that not during a long bend 30 secconds at any speed and on a left hand bend only. My ramp out of work is a slow 30-45 seccond left hander up hill. Twice in the last 3 days (the only times I've been up it) it's dumped the back end at the end of the bend causing a very loud bang as the back of the car hits a bump.

Anyway this happened and I set the suspension to raise and carried on slowly, and then again noticed the car hadn't risen (about the same time I went over a sleeping policeman (bang). I reset the suspension to go full up as I was sat at traffic. The back cave up the front didn't and I got a suspension fault Maxim 50 mph and a service light. I took it home 12 miles at around 30, car didn't bottom out, the suspension was deffo hight/mid at the back and normal at the front.

I have had the suspension warning come up before "Something else strange I noticed. I removed the head unit a few weeks ago and found that with out it the suspension errored and could no longer be raised or lowered, is that normal?" I thought, I wonder what happens if I take the head unit out now. So I parked up at home, took the head unit out and now I have working suspension no faults and the car didn't error at all on a 20 mins bumpy drive (single track country lanes). The car also comes up and down faster than it use to the suspension feels more controlled and less boaty, also after removing the radio the front suspension came up to mid high in a seccond or so.

Wtf is that all about!

I will continue trying to get the software installed to work, I am slightly amazing I didn't bgwt it working straight way what with being 3rd line IT and all!

[Xantippa]

Have you checked that the dog bones on height sensors are allright? I had another in the front disconnected and front end didn´t want to rise after that most of the times to normal driving height, though occasionally it was ok. Front end did go up and down however if using adjustment buttons, just didn´t want to stay at normal driving height.

If dog bones are all right and moving nicely (not rusted), check also this: http://c6owners.org/plugins/forum/forum ... hp?2638.30

[ActivaV6uk]

That was my first thought but apparently mine has 4x correctors so I probably have the wrong part.

[Xantippa]

I think dog bones are the same on all C5 X7 models. I checked the part number lately on service.citroen. So it doesn´t matter wether your car has 2 or 4 height sensors.

[ActivaV6uk]

That's great news I figured I had just waisted the cash.

[GiveMeABreak]

Hang on a second, some confusion here.... if you are saying you have bought parts, then no, they are NOT the same height correctors as they are on a 4 cylinder X7!

Xantippa, was saying that the movement mechanism may be similar, but they are not the same parts and have specific part numbers for each of the 4 units. There is a specific part left and right for both front and rear. So if you are saying you have bought parts for a 4 cylinder, they will not fit.

For your car they must be the correct sensor for each wheel, you cannot mix and match,

[ActivaV6uk]

It's a single dog bone I had bought, I had made the incorrect assumption that it was the same at the back for all c5's. The issue is getting worse, untill my last issue where the car errored it was staying up most of the time, now it's sagging over time, or dropping like a brick. And it's also taking an age to come up too, not all the time mind you but it's taken over a minute once, the other times it's up between 5 secconds and 30.

I need to rebuild the laptop I had setup for the diagnosis box, it's complaining that there are loads of dll's missing and they aren't the standard libraries as the replacement one I have are missing the calls required. I have a week off so there should be movement on this shortly

[GiveMeABreak]

Your best bet is a good diagnosis first of all. Let's examine all the stored codes and I strongly recommend when you do get it up and running that you make a note of ALL stored codes first, before clearing them and re-running the Global test. Reason being not all codes will be re-reported straight away as there may be intermittent faults. We do need to see what has been logged historically first to give us a few clues.

It is of course possible that your hydraulic valve block at the rear has that issue (linked to by Xantippa on the C6 site) where it is sticking and allowing rapid fluid return. If it were the height correctors (and bearing in mind that you have 4 of these) and if there were serious anomalies in the readings between say, the 2 rear correctors, I would expect the suspension ECU to throw a wobbly and log one of the myriad fault codes. For example:

There are 3 possible faults logged for EACH of the 4 height corrector sensors by the CSS (Suspension ECU specific to V6 models):

• Open Circuit or short circuit to -
• Short circuit +
• Inconsistent Value

The codes for eack of the three respectively are:

• C1152, 53 & 54 (Front Left)
• C1155, 56 & 57 (Front Right)
• C1158, 59 & 60 (Rear Right)
• C1161, 62 & 63 (Rear Left)

But at least you should be able to run some actuator tests ans see what the pressure is front and rear, average axle travel front & rear etc.

[Xantippa]

For me with my disconnected dogbone -problem there was not much help from diagbox, fault codes didn´t indicate where the fault really was. It´s so much easier to look under car and check wether linkages are connected and moving freely. Adding some lubrication at the same time is not a bad thing either.

[ActivaV6uk]

Not to jinx it but it looks like the install might work this time.

Nope won't install the diagbox again. This time DLLs are fine but the awroot_v7_conf+activation_v8.exe doesn't do its job. One thing it doesn't know is what should be files and directories, I checked the ones in question appear to be files. But otherwhis the software is still not registered which I was assuming it would be?

[GiveMeABreak]

Not sure what you have / are trying to do Andy; I can't make out what you are referring to in your post about checking files and the like???- but if this is a reinstall over an exiting version - it won't work.

Any reinstall has to be done after a complete removal and registry purge of all related files. Send me a PM if you need some help or want me to dial in.

[ActivaV6uk]

Firstly a formal thank you to Marc who has been amazing, Sunday morning we were still online (1am) trying to get diagbox installed on the laptop. As it turns out the broadwell and above CPU's don't look to be compatible with it so your looking for a core2 or possibly a sandy bridge based laptop to work with diagbox should you be building one.

Now I actually have some news. The back of my car is now working properly. So far only for this afternoon but some places where it always went down it no longer does nor does it anywhere else...

I pushed the button to raise the back of the car when the boot was opened, there was a buzzing/alarm from around the battery, the car didn't raise but as of that point I have had no issues. And the car corrects for height when I or others get in, which it didn't use to ..

I'd say it's a fluke but I thought I'd feed this back to you all.

[GiveMeABreak]

No worries - a challenge that one!

Good new that it seems to be behaving Andy. The Processor info will be useful for future reference and may help others with install issues.