Help Identifying Some Connectors...

Afternoon guys....

I've recently aquired a '95 VSX 2.1TD manual.... that used to be a 2.0TCT auto.
Yes, it is a bit weird, and its come with an equally 'interesting' set of problems.

The past few days, I've just been having a general look around, doing fault rectification etc

Anyway, today, while investigating the possibility it may have cruise control, I discovered several stray connectors in the engine bay. I have taken some pics of these in the hope that someone here may recognise what they are and where they go....

I don't think the forum allows images to be links, so I'll post some thumbnail pictures with a text link to the fullsize photo....

First, are these two connectors on top of the thermostat housing, at the right of the engine:


Fullsize pics here and here.

The next thing, is this orange connector that is connected to a grey cable, which comes from somewhere underneath the thermostat housing:

Fullsize pic here.

Then, beside that, theres this white connector with two grey wires, which appears to come from the bottom of the diesel filter...

Fullsize pic here.

Lastly, theres these two, which aren't electrical, but someone may know what they are..
Theres these disconnected pipes bolted to the side of the engine, above the thermostat housing:

Fullsize pic here.
I presume that may be some kind of diesel preheater ?

...and this rubber hose that comes from a hole in the metal between the plastic ECU box, and the driver's side headlight:

Fullsize pic here.
I suspect that's something to do with the headlight washers, but I'm not sure.

Sorry for the long post and numerous pictures. If anyone recognises any of these connections, or has an idea why they may have been ripped out, I'd appreciate your opinion.

Many thanks

Ciarán.

This post has been edited by Ciaran on May 09, 2006 05:46 pm

Hi Ciaran

It looks as though the TCT engine bay wiring loom was left in situ when the engine swap was done.
The headlamp washer pipes join in the drivers side of the front bumper then the supply pipe comes into the engine bay about where you have found your loose pipe.
Diesel fuel heaters are routinely cut out to cure poor starting problems on both 2.5's and 2.1's. I guess anyone putting a diesel engine in a former petrol car will cut out the fuel heater rather than take extra steps to include it.
Diesel filters have a water in fuel sensor in the base, the car will not have had wiring through the front bulkhead for this so I suspect it was left unconnected.
I suspect that the second sensor on the thermostat housing comes under the same heading.
I wonder which ECU is fitted to the car. I suspect that it has to be the diesel one that came with the engine so hence no cruise control.

Regards

XMexc

Hello again ,

Oh, joy , I suspect this is going to be fun...

Hmmm... that makes sense. Where abouts does the reservoir live, in the wheel arch or something ? I can see the filler neck, but not much else...

I see. Come to think of it, my Xantia is never done complaining about this when its been left for a while, so I can't say I'll miss the warning. I'll drain it anyway...

What's interesting about this is there are 3 connctors on top of that thermostat housing. The middle one is plugged in, yet the other two aren't. Did you mean these, or the orange connector with the grey cable ?

On the subject of ECUs, I'm not sure whats in it, will have a look tomorrow and post back, should be interesting...
Is it possible to make cruise work another way, or does the ECU have to be aware of it ?

Thanks again for your continued help XMexc, much appreciated

If it has a '95 or before engine, it wont have an engine ECU as they all had mechanical injection until 96/97. If the throttle cable is connected to the fuel pump its mechanical.

Peter.N.

Well that puts that particular question to bed then, thanks Peter.

So, I'm presuming cruise isn't possible on the early mechanical diesels with no ECU ?
I wonder why that vacum solenoid is on the pump though... this is getting confusing

Hi Ciaran

For the later cars with electronic throttle control the cruise ECU is just part of the programme in the main ECU. Plug in the two switches and on the next ignition switch on the cruise system is recognised and enabled ready for use.
There is a self help file explaining how to do this for a 2.5TD.
This system cannot work without the correct main ECU for the model of car.

The earlier VAC cruise system as first fitted to Mk1 cars has its own cruise ECU module and the system is independant of the main ECU. This system could be fitted to virtually any XM. To my knowledge Citroen were still using it on Mk2 V6 auto's as late as 1995. It looks as if your converter tried to fit it to your car when the diesel engine was put in. That does not mean that he was successful. Someone else was on this web site a few days ago asking where the cruise control relay was located and we could not help him. Unfortunately if we cannot tell you which bits you should have and where they should be located then you have a real task on your hands. Still if you crack it then you will have the makings of a very good self help file.

Regards

XMexc

Hi again,

I'll have to do some further investigation at some point, but sadly priorities and finances at the moment mean I have to concentrate on getting the necesseties (read, headlights) working. Definately a potential project I want to come back to though.
To my knowledge, the car only has two ECUs in the box. Which appear to be suspension and ABS, though it does have an unconnected plug for a third one. There's quite a lot of mystery surrounding what work was done and where and why, and I would have asked the previous owner, but sadly he died about a year ago. Things like the immobiliser code died with him, thankfully it's in neutral mode. Indeed, it's interesting that the immobiliser works at all, if theres no engine ECU.... but it's definately active, and beeps and flashes in all the right places. If it is indeed operational, I would love to know the code, as I really would prefer the immob to work, especially when I leave the car parked outside work for long periods etc. I know this is a next to impossible task though, so will stick with the obtainable for now.

Thanks once again for your advice

Ciarán.

Hi Ciaran,

Sorry to disappoint you about the cruise control but here are what your pictures show:

Picture 1+2
Temperature sensors on the cylinder head outlet tank. The sensor with no connector fitted and only one connector spade is usually the one for the dash temperature sensor. Do you have a dash temperature gauge? If not, thy have plugged the hole in the tank with a sensor but there's no electrical cabling to link it to the dash.

Picture 3
I don't recognise the connector and I'm not at home at the moment so I can't check. Sorry I cant help you with that one.

Picture 4
There is a water detection sensor at the bottom of the diesel filter housing. There are two cables leaving the bottom of the housing terminal terminating in the plug/socket shown in your photo. Where is the other half of the connector? Does it fit into the connector in Photo3?

Picture 5
This is the diesel preheater. It is bolted to the side of the cylinder head and preheats the diesel prior to injection for environmental (and temperature) reasons. However the block which the diesel passes through is made from sintered zinc alloy and the sintering process has failed. The granular nature of the incomplete sintering process leaves the block porous. It is a famous leakage point for air getting into the diesel system since it is at negative pressure at that point. In most XM's this has been bypassed by linking past it with some tubing. No harm will come of doing this since very few XM owners live in such cold climates where this would make a difference. The two copper tubes you see in the photograph are the inlet and outlet connectors to the preheater block.

Picture 6
Its hard to tell but I think the hose in your photo is not a hose at all. If it has a tapered section just where it meets the body then its a fixing for the plastic box in which the ECU's are housed.There will be a hole or a fork in the plastic casing and the 'hose' will pass through it and the tapered part will slip over some part to keep it from coming loose.

Sorry as I say for not providing cruise control related answers but thats how it goes.

Cheers

noz

Picture 6, the hose looks like the one that leads to the charcoal canister under the front wing. All tank vents are connected to the canister on petrol models. any vapours given off are adsorbed by the charcoal. The hose that you show was connected to the inlet manifold, via a couple of ecu controlled valves, to allow the engine to breath in the adsorbed vapours.

Hi Ciaran

Have had a look at a Mk2 with the drivers side wing removed. The headlamp washer tank sits at the top just under the wing. The feed pump is outside the chassis right opposite the EC box. There is a nice sized hole in the chassis to poke the unused washer feed pipe out of the way. If this was done it would appear in the engine bay just like the loose hose end you are trying to identify.

Regards

XMexc

Hi Noz,

Thanks for the detailed reply.

Yep it has a temperature gauge and it's working. Is that outlet tank specific to the diesels, or would it have been the same on the TCT ?

No, they are both male connectors, the orange one having three spades and the white one too. Tried to trace the wiring of the orange one today but can't see where it goes without removing things...

Don't worry about it, the cruise is the least of my worries to be honest, at the moment I have one working sidelight (everything else lightwise dead), a pump that squeals when put under load, and a 'creative' carphone installation to contend with

Thanks very much for your replies.

This post has been edited by Ciaran on May 11, 2006 10:59 pm

Interesting arrangement. I presume this isn't used on diesels ?
I've also been considering the suggestion that its the feed to the headlight washers, especially since that side isn't washing....

This post has been edited by Ciaran on May 11, 2006 11:00 pm

Hi XMexc,

When you say unused pipe, do you mean excess slack in the pipe ?

Having the end of the pipe poking up like that gives me the impression that its disconnected...

Oh yes,

Just to compound matters, I've found another connector, this time going to some device that's mounted to the diesel pump...


(Fullsize pic)

The wiring runs to this plastic black thing on top of the pump:

(Fullsize pic)

Beats me what it's for !