2006 C5 Hydractive 3+ - No connection to Suspension ECU with Lexia

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olliejolly
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2006 C5 Hydractive 3+ - No connection to Suspension ECU with Lexia

Post by olliejolly »

Hey folks.

First post here, thought I'd best register instead of lurking, I'm ashamed to say this isn't my first French car (my first in 2013 was a Citroen) so I really should have signed up sooner.

Anyway, I bought my 2006 C5 Estate back in May and I love it. It's the 2.0 HDi Exclusive, with the 6-spd automatic gearbox, sat nav, sunroof, hydractive 3+ and all the other good stuff.
It's a bit rough, but I'm getting there with it.

I have DiagBox installed on my Vaio (Core I7) laptop with Windows 7 Pro 32-Bit, initially I had it running V7.57 and didn't feel the need to update further as it was all working okay, with the exception of the Suspension ECU which won't connect.

I ran a General Test on Lexia several times and every single other ECU on the list would connect fine and worked for config/actuator testing etc.
I thought I'd try updating just in case it was some funky version issue, so updated to 7.83, and unfortunately it's still no good.

I get "NO" in the Dialogue field on the list of ECU connections, selecting the Suspension ECU brings up the "SUSPENSION_ECOTECH" option, selecting that presents "No dialogue with Ecu during initialisation Validate for a new test or press Return key"

The relay sounds like it clicks in the cable, so I'm not convinced it's that at fault, it was a new cable from eBay and works with everything else as I say.
I took off the multiplug at the front of the pump unit, sprayed some contact cleaner, gave it a few wiggles etc, but still no good. The diagnostic port in the glovebox all seems okay too, although it's a bit spaghetti in there with all the wiring (including a RAC "Smart-Nav UK" box which I can only assume is for the in-car sat nav.)

The suspension works fine, goes up and down, the ^ v and Sport button all work, as does the height button in the boot. It's just the diagnostics that won't connect, and I'm not sure what to do. I don't have access to another cable/Lexia installation that I can try, nor access to another C5 to try my cable with.

My main concern is that it's going to cause me problems at some point as I could do with doing some maintenance on the spheres and pump, etc, and I can't currently without being able to connect.
The car also came with 205/50 R17s on it from a C4 for some reason, so I could do with checking the ride height is still correct now that I've put it back on 215/55 R16s.

Does anyone have any suggestions or ideas on what I could try to see if I can narrow down the cause? I can't see where the wiring goes other than down the back of the pump and up the wing, nor can I even get a multimeter prong into the multiplug to test the pins (even if I knew which to test).
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GiveMeABreak
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Re: 2006 C5 Hydractive 3+ - No connection to Suspension ECU with Lexia

Post by GiveMeABreak »

Hi and welcome.

First - no! - that RAC box you have is nothing to do with the car - it has been added at some point by a previous owner! That being the case, there's no telling what it is unless you can locate the foreign box connected to the wires with some data on that we can try and identify - maybe it's something like an insurance black box... but if it was me, that would be the first thing to go.

Back to the suspension. Did you buy a cheap kit off ebay? If it's not a full chip revision 'C' kit with all the hardware you will have communication issues with some multiplexed CAN vehicles like the C5. Sometimes you may find in the small description something about their kits not working with the C5.

Most decent UK sourced Full kits are about £100 - so if you've paid sub £40. I would suspect you may have a cut down version and that may be why you can't connect to the suspension ECU.
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Re: 2006 C5 Hydractive 3+ - No connection to Suspension ECU with Lexia

Post by GiveMeABreak »

Here's the sort of spiel they put out - this one being a £55 kit:
For Citroen cars including, C1,C2,C3,C4,C6,C8,C-CROSSER,NEMO,BERLINGO,JUMPY,JUMPER,AX,SAXO,BX and so on.But please pay attention,according to our customer's experience,this item can not works good at C5 new models.
Note, they can't even spell Citroen correctly.....
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myglaren
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Re: 2006 C5 Hydractive 3+ - No connection to Suspension ECU with Lexia

Post by myglaren »

I think the spelling fairy has fixed the spelling in the quote.
olliejolly
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Re: 2006 C5 Hydractive 3+ - No connection to Suspension ECU with Lexia

Post by olliejolly »

Hi Marc, and thanks.

You might well be right, I was aware of that being a risk although I'm wary about spending another £100+ only to find out it's actually a physical problem with the wiring or something, haha!
The one I purchased is item number 154070385720 (remove that if needed)
I suppose the other option would be to take it to a specialist and ask them to plug it in, if it works for them then I would probably buy a decent one myself.

For the RAC thing, I did get a picture of it:
DSC_3074.JPG
It's tucked behind that pop-out panel on the side of the glovebox, visible when you open the door. Flashing red light on it, and has a round aerial looking thing stuck to the windscreen behind the mirror too.
Not too bothered about it being there really, it looks fairly well wired-in so I don't really want to go pulling it out and risk disconnecting something else, but I may unplug it if it's not an original accessory or something.

Incidentally, now I look at it, it was added in May '06 and my car was registered in March, so must have been added after-sale.
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Re: 2006 C5 Hydractive 3+ - No connection to Suspension ECU with Lexia

Post by GiveMeABreak »

Right that's a Smart Nav MC45 - it's an aftermarket Sat Nav unit - so a bit ancient now - a few of them on ebay. I'd be interested to know if they have replaced the multifunction screen with the one that comes with this or whether it is separate? The Factory fitted units units for this year were the RT3/4 systems with large colour screen - so maybe it had a fault and they fitted this aftermarket system. I would be wondering whether that has compromised other vehicle functionality as a result...

Do you have your VIN so I can see what you had at factory? A picture of the MFD display screen would be useful to.
olliejolly
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Re: 2006 C5 Hydractive 3+ - No connection to Suspension ECU with Lexia

Post by olliejolly »

VIN is VF7**************[VIN obfuscated, can be read by forum staff].
DSC_3083.JPG
- RT3 I believe? Seems standard to me, but I'm no expert. CD in the player is a NAVTEQ "ON BOARD Cartographic CD with the Major Roads of Europe" IT/Telecoms System, 2005/2006 second edition.
DSC_3084.JPG
That's the glovebox, you can see the wiring for the Smart Nav, it's off to the left behind the left wall of the glovebox, that 3.5mm jack is part of it.
DSC_3085.JPG
DSCPDC_0003_BURST20210723154506666_COVER.JPG
That's (what I assume to be) the GPS aerial. Say hi to Cecil.

Might as well add these too from yesterday evening's trouble-makingshooting session:
DSC_3075.JPG
DSC_3076.JPG
wheeler
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Re: 2006 C5 Hydractive 3+ - No connection to Suspension ECU with Lexia

Post by wheeler »

My thoughts on this are it's you kit that's the issue.
If this was a vehicle fault & there was no communication with the suspension ECU It would mean one of 3 things, Either...
1. The suspension ECU is dead.
2. The Suspension ECU is not powered up.
3. There is a break in the diagnostic line between the suspension ECU & the OBD socket.

If you had scenario 1 or 2 your suspension wouldn't operate and all the other ECU's on the HS CAN would have faults logged in them for communication with the suspension ECU.
(What is you fault code in the engine ECU out of curiosity?)

Scenario 3. There is no direct connection between the suspension ECU & the OBD socket on this car, fault info is transmitted from the suspension ECU on the HS CAN to the BSI then from there to OBD socket. You can probably guess that if there was an issue on the CAN lines you would have lots serious issues & the car would not start either.
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Re: 2006 C5 Hydractive 3+ - No connection to Suspension ECU with Lexia

Post by GiveMeABreak »

olliejolly wrote:
23 Jul 2021, 15:56
RT3 I believe? Seems standard to me, but I'm no expert. CD in the player is a NAVTEQ "ON BOARD Cartographic CD with the Major Roads of Europe" IT/Telecoms System, 2005/2006 second edition.

That's the glovebox, you can see the wiring for the Smart Nav, it's off to the left behind the left wall of the glovebox, that 3.5mm jack is part of it.

That's (what I assume to be) the GPS aerial.
I had one of these.
Yes that's the RT3 and looks unmodified - not standard - was top of the range at the time.

If it 's the system I'm thinking about, it was a Trafficmaster solution with various options and is supposed to have a small LCD screen that is attached to it. I would get rid of it as it's nothing to do with the original RT3 and yes, the NAVTEQ CD is the mapping data for the unit for the specific year. You load in different countries form the various multi CD pack that came with it - I suspect you have the UK loaded - so leave it as it is, although it will be well out of date by now. That may be another reason for fitting an aftermarket solution that itself is likely now longer supported now and is useless without the screen in any case.
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KennyW
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Re: 2006 C5 Hydractive 3+ - No connection to Suspension ECU with Lexia

Post by KennyW »

I would check your diagnostic cable as this was the problem with mine.All worked except the suspension ecu.
I take the suspension works fine.
Worth finding another member to use their Diagbox to check all evidence are talking

Kenny
olliejolly
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Re: 2006 C5 Hydractive 3+ - No connection to Suspension ECU with Lexia

Post by olliejolly »

That all sounds reasonable, thanks everyone.
It seems like I got a bit lucky with the spec of the car actually, I think the only extra it doesn't have is heated seats.

I think I'll have to try and find someone local with a decent cable, or as I say an actual Citroen specialist. Probably going to Blackpool over the next couple of weeks anyway (I go often) so might drop in up there.
wheeler wrote:
23 Jul 2021, 20:07
(What is you fault code in the engine ECU out of curiosity?)
I'm not entirely sure off the top of my head, but I remember a glowplug message, and also EGR related. Nothing I'm worried about.


Thank you again for all your input.
Ollie