Xantia Cruise Control Questions

pottsy · Post by **pottsy** » 20 Jul 2008, 11:59

Greetings all.

I've just joined this Esteemed Forum as a result of my involvement in the Aussiefrogs Forum in Orstraylia.

My background is in French cars as an owner and fiddler. I'm a hobby mechanic by inclination rather than profession, so anything I claim to be fact may need to be subject to a reality filtering process.

That being said, I have a DS and a Xantia that I love dearly and enjoy playing with. It's to this end that I come on bended knee to the acknowledged home of the Citroen Gurus.

My Xantia is a lovesome beast, but sorely in need of cruise control to make those long drives between corroborees a bit less tedious.

I have obtained most of the goodies required from a dead donor car, but the biggest stumbling block appears to be tha fact that no-one can tell me where to find the cruise ECU.

One source claimed it was under the centre console. I found a largish grey unit there, but further research proved it to be the central locking controller. At the forward end of the centre console, under the oddments tray, there's a controller for the air bag and pre-tensioner's. I intend obeying the dire warnings about this box and steer well clear of it. Adjacent to this unit, however, are a number of unused plugs which may well have a bearing on the search. The wire numbers discernable on these plugs unfortunately fail to match up with any of the ones for the cruise system, so this may be a dead end.

Another source has provided a pair of wiring diagrams for the cruise system complete with a diagram of a left hand drive car showing the ecu to be situated behind the facia in front of the passenger. Acting on this information I figured I'd have a look under there for an unused plug that might match up, but I can't even get the bloody glove box out, so gaining access to under there is still a closed book.

So there we stand at present. I plan to visit the donor car and seek a bit more carefully for anything remotely resembling an ecu, but if anyone of you Xantia Gurus (What is the collective noun for gurus? Perhaps an Om of gurus?) can shed light on my quest, I'd be eternally grateful.

Car is a 1996 series 1 "Image" auto estate, called Zaphod for reasons which probably would be hard to understand in the UK. Ask me to explain one day!

Cheers, for now, Pottsy

Post by **myglaren** » 20 Jul 2008, 13:01

I have no advice to offer pottsy but welcome to the forums.
Someone who does know will surely ba along sooner or later, depending on the weather and when the pubs close

Has your car two heads and three arms?

pottsy · Post by **pottsy** » 20 Jul 2008, 13:14

Steve

Apart from the obvious alliterative euphony of the name "Zaphod the Xantia", we actually bought the car in Tasmania, a state of Australia which (perhaps apocryphally) has such a small gene pool that the denizens are largely duo- cephalic!

And my wife and I are both aficianados of Mr Adams work.

I shall await the arrival of closing time with bated breath!

Cheers, Pottsy

Post by **CitroJim** » 20 Jul 2008, 13:37

Welcome to the forums Pottsy, it is always a pleasure to welcome another from down-under

I'm no stranger to the place, having lived in Darwin for a time. Our daughter Robyn (good Aussie name

) was born there.

pottsy wrote:we actually bought the car in Tasmania,

We spent two idyllic weeks in Tas on holiday, love the place to bits

We went there hoping to find cold and escape the opressive heat of Darwin. It was cooler but the welcome from the Tassies was incredibly warm

pottsy wrote:And my wife and I are both aficianados of Mr Adams work.

Me too.. A genius if ever there was one.

Now, onto your cruise control Pottsy, before I drift so off topic and descend into HHGTTG territory

I'll have a close look at my stash of wiring diagrams and related info. Firstly, what engine is it?

So long, and thanks for starting this thread...

(sorry, I'll get my coat...)

pottsy · Post by **pottsy** » 20 Jul 2008, 13:45

Jim

It's the 8 valve 2 litre. (XU10J2C I believe?) with the ZF 4HP14 4 speed auto.

Items I have so far are:

The steering column stalk.
The dashboard switch.
The vacuum pump (from under the LH bumper end).
The associated venting valve with the pump.

I'm given to understand that the plugs required should be already on the loom?

I'd welcome any documentation you can provide.

The legendary Mrs P and I just returned from Darwin a week or two ago after a pleasantly hedonistic holiday driving a Nissan Patrol from Broome in the northwest to Darwin via the Gibb River Rd, the Bungle Bungles (Purnululu national park), Katherine and Kakadu.

It was my second visit to Darwin. A great place to visit but I think Melbourne suits me better in the Summer.

And Tasmania has some of the best driving roads in the World, in mybiased opinion!

Cheers, and thanks in anticipation, Pottsy

DickieG · Post by **DickieG** » 20 Jul 2008, 14:02

If your car is a Series 1 then the cruise control relay is normally situated within a large triangular box located on the O/S/F wheel-arch behind the wheel. Pullout the arch liner then undo a nut at the top/front of the box and it will pull out.

As to where the ECU is however I'll have to have a think on that one.

Do you have the correct brake pedal switch?

Stempy · Post by **Stempy** » 20 Jul 2008, 16:01

The cruise ECU on mine is under the handbrake in the centre console, but it's a mk2 and I think they moved all the ecu's to different locations on these. Mine is a small silver bare metal box if that's any help.

Toby_HDi · Post by **Toby_HDi** » 20 Jul 2008, 16:06

If possible keep us updated on your project. Retro fitting cruise control is something I want to do as well, not sure I can though as I have the HDi engine

Stempy · Post by **Stempy** » 20 Jul 2008, 16:14

Stempy wrote:The cruise ECU on mine is under the handbrake in the centre console, but it's a mk2 and I think they moved all the ecu's to different locations on these. Mine is a small silver bare metal box if that's any help.

I mean the ECU not the car

pottsy · Post by **pottsy** » 20 Jul 2008, 23:59

DickieG

No, haven't yet salvaged the brake light switch from the wreck. By dint of some contortions with a mirror I've determined that there are three wires heading for my existing one, but until I pull it out and check I have no idea whether it's got the break contact as well.

Interestingly, the diagrams I've got so far show the cruise cars as having the different switch, with a break and a make contact wired as a changeover and three wires coming out of it. The diagram, however, shows no connection to the break contact! This may be an oversight of the draughtsperson.

If it's all too hard to fit the right switch, I'll dummy it up with the safety relay as all it does is signal the ecu to stop controlling (by breaking a dc path to one of the ecu pins.)

Appreciating all the thought being put in, chaps. Don't stop now on my account!

Cheers, Pottsy

pottsy · Post by **pottsy** » 25 Jul 2008, 08:28

Still trying to find out where the cruise ECU is chaps. I managed to carefully remove the glovebox from the donor car hoping to find the magic box inside, but it was not to be.

The unit inside the left front wheel arch/bumper end is the vacuum pump and vent valve. I've got that bit out. I can't see any unused connectors under there that match up. There is one under there that's a multi-pin jobbie, but it's also unused on the donor car, so I'm discounting that as being the ECU connector.

I'd love to solve this puzzle. Please interpret that as begging in an ingratiating and non-threatening way!

Your's pleadingly, Pottsy

pottsy · Post by **pottsy** » 31 Aug 2008, 01:51

Well the mystery is still just that, a mystery.

Discussions with several people distilled down to the cruise ecu being either (1) behind the facia LHS on top of the heater box,(2) in the centre console or (3) under one of the seats.

The donor car has now had the dashboard assembly completely removed and we simply can't find anything resembling a cruise ecu in there. The centre console only contained the aforementioned boxes. Under the seats is not looking good either, but they have yet to be removed.

I have a photo of the right unit so we know what we're looking for but this is turning into a major frustration.

Still looking for Guru Guidance!

Cheers, Pottsy