I am also P£$$$ed with hydractive

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

Moderator: RichardW

Deanxm
Posts: 3327
Joined: 18 Dec 2008, 17:57
Location: Isle of wight
My Cars: Citroen XM
x 87

Re: I am also P£$$$ed with hydractive

Post by Deanxm »

i think the issue is the chip that this information is stored on is not re writable.

D
XM Prestige PRV6 92
Talbot Express Autotrail Chinook 89
Mitsubishi L200 Trojan 14
Xantia Activa 95, sold (missed)

Service Citroen is awesome, it shows me pictures of all the parts i used to be able to buy............
addo
Sara Watson's Stalker
Posts: 7098
Joined: 19 Aug 2008, 12:38
Location: NEW South Wales, Australia. I'll show you "Far, far away" ;-)
My Cars: Peugeot 605
Citroën Berlingo
Alfa 147
x 93

Post by addo »

Even if it's PROM, not EPROM, I'm sure there is a solution. Will be waiting to hear John's thoughts on it.

Has anyone ID'd it?
Deanxm
Posts: 3327
Joined: 18 Dec 2008, 17:57
Location: Isle of wight
My Cars: Citroen XM
x 87

Re: I am also P£$$$ed with hydractive

Post by Deanxm »

yeah John will know.

D
XM Prestige PRV6 92
Talbot Express Autotrail Chinook 89
Mitsubishi L200 Trojan 14
Xantia Activa 95, sold (missed)

Service Citroen is awesome, it shows me pictures of all the parts i used to be able to buy............
addo
Sara Watson's Stalker
Posts: 7098
Joined: 19 Aug 2008, 12:38
Location: NEW South Wales, Australia. I'll show you "Far, far away" ;-)
My Cars: Peugeot 605
Citroën Berlingo
Alfa 147
x 93

Post by addo »

I just want to see the code opened up! The we can all play silly buggers and tailor it suiting a personal preference - rather than swapping boxes.
xmexclusive
Posts: 419
Joined: 18 Dec 2008, 22:50
Location:
My Cars:

Re: I am also P£$$$ed with hydractive

Post by xmexclusive »

Will turn out a H4 and a H5 suspension ECU and look at the chips to see what I can identify for data storage.
The H4 may be an one shot EPROM but the H5 is likely to be a one shot EEPROM or similar.
Not looked at them from this point of view as reading the data storage was fairly low down on my list.
Not all Mk2 XM models have the same suspension parameters, the 2.5TD has to be different.
Still that would give me two different sets of data to use to identify storage location.
Think somewhere in the workshop manual it lists the parameter differences.

John
Xmexclusive
User avatar
DickieG
Monaco's youngest playboy
Posts: 4877
Joined: 25 Nov 2006, 09:15
Location: Buckinghamshire
My Cars:
x 38

Re: I am also P£$$$ed with hydractive

Post by DickieG »

xmexclusive wrote:Not all Mk2 XM models have the same suspension parameters, the 2.5TD has to be different.
What makes you think that John?

Other than allowing for later differences such as S2 Xantia's having the brake pressure switch removed, IIRC there are three programs, XM, Xantia plus Xantia Activa, which means that a 90 bhp Xantia TD uses the same program as a 194 bhp V6, the difference in handling between a TD and V6 Xantia is achieved by using different sphere's and struts, I'd have thought that XM's were similar.
13 Ram 1500 Hemi
14 BMW 535D Tourer
19 BMW i3s
06 C3 Desire 1.4
72 DS 21 EFi Pallas BVH
xmexclusive
Posts: 419
Joined: 18 Dec 2008, 22:50
Location:
My Cars:

Re: I am also P£$$$ed with hydractive

Post by xmexclusive »

Hi DickieG

The use of a different suspension ECU for the 2.5TD was listed in the Citroen Workshop Manual (1995 Model Year General specification).
It states this change was to alter the hard/soft control to suit that models specific needs.
I realise that Citroen were probably happy to treat all Xantia with a one standard will do approach but not so the XM it seems.

The workshop Manual also specifically bans the interchange of ECU's between cars using different parameters.
I particularly liked:
IMPERATIVE: do not fit a CITROEN XANTIA hydractive suspension ECU to a CITROEN XM and reciprocally.


Hi All

Have checked a few Hydractive 2 suspension ECU's.
Code marking on H4 and early H5 types gives vehicle and model coding.
These will be mostly XM ones:
H4 S2G2G
H4 S2G2G
H4.3 S2I2G
H4 S2J2G
H5 S2J2G
H5 S3A2G
H5 3B2G

H4 / H4.3 / H5 is the generic ECU version number.

S2G2G is XM standard soft/firm mapping.
S2H2G is XM 2.5TD soft/firm mapping.
S2I2G No information, will update if I find anything.
S2J2G is the first ECU version to contain selectable suspension tables for all hydractive cars (during 1996 model year).
H5 S2J2G was a major electronics revision of the H4 S2JG ECU (during 1997 model year).
H5 3B2G was the ECU version on which there is no provision for monitoring the brake pressure switch (during the 1999 model year).
Citroen also made this the only ECU available as a spare part (telecoding to suit car/model required).
They confirm that it may be retrofitted to earlier cars but will render the brake pressure switch inoperative.

Will add in any Xantia ECU information as I turn it up.
Edit note:
Xantia programmable replacement Hydractive ECU's. Introduced Jan 1995. (source BRE0085GB Add No. 2).
Xantia with Hyractive - ECU marked 96 231 919 80. White & Black plugs.
Xantia with SC/CAR - ECU marked 96 144 951 80. White & Green plugs.

Xantia (non SC.CAR) changed from H5 3A2G to H5 3B2G ECU from RPO No. 7901.
This change of ECU renders the brake pressure switch inoperative if fitted to an earlier Xantia. (source BRE0085GB Add No.11).

Understand now why I put the chip reading on hold.
The H4 ECU's have a TMS3700056 microcontroller to run things.
I think this contains the programme once only memory.
The micro is a 68 pin direct soldered chip.
I can remember obtaining its data sheet and I think reading that put it to the bottom of the heap.
I will open some of the later ECU's, particularly the H5's when I get the chance.

A bit of interesting "anorack" picked up on this trawl was that the thread on the hydraulic pump changed at RPO No. 7483.
Seems the Pressure regulator unions changed at RPO No. 7252 (source BRE0031GB Add No. 2).
Then all Hydraulic suspension unions changed at RPO No. 8057 (source BRE 003GB Add No. 3). Strut head & rear cylinder unions plus Suspension Regulators(front and rear) all changed from Standard ISO connections to Citroen specials.

John
Xmexclusive
User avatar
DickieG
Monaco's youngest playboy
Posts: 4877
Joined: 25 Nov 2006, 09:15
Location: Buckinghamshire
My Cars:
x 38

Re: I am also P£$$$ed with hydractive

Post by DickieG »

Hmm I wonder why the 2.5 needed an different program, as it's hardly a road burner I presume that the 2.5 diesel lump must have been so heavy that the suspension was switching to firm too late when negotiating large undulations and causing the suspension to bottom out.

Re the ECU numbers I have two Xantia ones in front of me right now, one programmed in week 26 of 97 that has S2J2G printed on it, part number 96 2421 7180 and another from 36/99 with S3B2G and part no 96 3180 8480.
13 Ram 1500 Hemi
14 BMW 535D Tourer
19 BMW i3s
06 C3 Desire 1.4
72 DS 21 EFi Pallas BVH
davetherave
Posts: 880
Joined: 01 Apr 2009, 21:06
Location: Norwich
My Cars:
x 4

Re: I am also P£$$$ed with hydractive

Post by davetherave »

Interesting, well perhaps tomorow ill fit the estate ECU and report back with my findings. I think we just need to save ECUs from scrap Xms.
(95) XM Silver 2.1td Exclusive.
(87) Cx 2.5 DTR T1 undergoing major cosmetic surgery.
GPZ500s
xmexclusive
Posts: 419
Joined: 18 Dec 2008, 22:50
Location:
My Cars:

Re: I am also P£$$$ed with hydractive

Post by xmexclusive »

Hi Dickie

Thanks for adding those Xantia numbers.
Thought it was worth collecting all the information in one place.
I guess we will eventually find a proper home for it.
I was actually mainly searching out the different types of pipe fitting Citroen used for my flaring tool project.
On the 2.5 XM it is in my opinion second only to the V6 in performance.
The balanced and axially mounted engine with its high torque set it aside from most other types of XM.

John
Xmexclusive
xmexclusive
Posts: 419
Joined: 18 Dec 2008, 22:50
Location:
My Cars:

Re: I am also P£$$$ed with hydractive

Post by xmexclusive »

Hi Dave

Been collecting for a while now.
Found a pile of 15 to do the above check.

John
Xmexclusive
davetherave
Posts: 880
Joined: 01 Apr 2009, 21:06
Location: Norwich
My Cars:
x 4

Re: I am also P£$$$ed with hydractive

Post by davetherave »

Your sorted for a while then!
I have resoldered one of the vno5ns on mine a while back when I had a similar issue, I wonder if the replacment chip has died too.
(95) XM Silver 2.1td Exclusive.
(87) Cx 2.5 DTR T1 undergoing major cosmetic surgery.
GPZ500s
xmexclusive
Posts: 419
Joined: 18 Dec 2008, 22:50
Location:
My Cars:

Re: I am also P£$$$ed with hydractive

Post by xmexclusive »

Sorted, perhaps but still thinking about buying another two that are currently on ebay.

John
Xmexclusive
davetherave
Posts: 880
Joined: 01 Apr 2009, 21:06
Location: Norwich
My Cars:
x 4

Re: I am also P£$$$ed with hydractive

Post by davetherave »

Well I have fitted the ECU from the estate and the suspension is still solid! arghhhhhh
(95) XM Silver 2.1td Exclusive.
(87) Cx 2.5 DTR T1 undergoing major cosmetic surgery.
GPZ500s
addo
Sara Watson's Stalker
Posts: 7098
Joined: 19 Aug 2008, 12:38
Location: NEW South Wales, Australia. I'll show you "Far, far away" ;-)
My Cars: Peugeot 605
Citroën Berlingo
Alfa 147
x 93

Post by addo »

Going back to basics a little here - are all spheres up to spec on pressure and orifice sizing?

If you have access to a signal generator and amp, you could try driving either electrovalve independently,to see if they each behave.
Post Reply