Earth Points

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KennyW
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Earth Points

Post by KennyW »

Hi All,

Does anyone have a definitive list of the locations of the earth points on the MK1 and MK2 Xantias.

Kenny
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Post by VertVega »

In mine, there are two wires coming off the negative terminal.
One large-diameter wire goes from the battery negative terminal to the gear box.
The second wire goes to the "chassis ground hub" (don't know the official name)
as seen in pic below:
Image

Gear box connection point can be seen looking down from the gap,
as marked in the pic:
Image

Chassis - Gear box (and engine) together makes up the "common earth".
Doors, hood and tailgate are also connected to this common ground with wires.
C5 II 2.0i 16V - 2005 - Estate - 103KW - EW10A - Petrol - Manual
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Post by KennyW »

Thanks for the reply,

I've checked these ones and given them a good clean.

I am interested in the earthing points for the instrument panel. Are they part of this cluster.

Kenny
C5 x7 2.0 HDi 160 hp Estate exclusive, the newbie
Xantia 2.0 Hdi 90hp 1999 only 189,000 and rising!!!!!!! Moved on to a new home
C3 1.4 petrol (SWMBO)
Xantia TD 1.9 Mk 2 Estate LX 1998 model over 210,000 miles now and still rising!!!!!!!!!!!!! now deceased 17/12/2010.
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Post by CitroJim »

Kenny,

There are earth point all over the place. There's hundreds of them. Best to tell what the problem is and then we can direct you to the most likely earth point(s).
Jim

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Post by KennyW »

Hi Jim,

It part of my starting problem re the fitting of the pump.

I think I've got the problem narrowed down to an electrical problem,not
mechanical.

Hence I am looking at the earthing points assocviated with the wiring.

Kenny
C5 x7 2.0 HDi 160 hp Estate exclusive, the newbie
Xantia 2.0 Hdi 90hp 1999 only 189,000 and rising!!!!!!! Moved on to a new home
C3 1.4 petrol (SWMBO)
Xantia TD 1.9 Mk 2 Estate LX 1998 model over 210,000 miles now and still rising!!!!!!!!!!!!! now deceased 17/12/2010.
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Post by CitroJim »

I'll have a look at the diagrams for you Kenny...

That'll be a job for tomorrow now... Remind me if I forget :wink:
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Post by CitroJim »

Hi Kenny,

Here are the full diagrams of the electrical side of the MK2 XUD9 Injection system:

Circuit Diagram

Harness Diagram

Component Locations

Earths in the circuit diagram are referenced by an M number (M for merde - yes, really :lol:) You know what merde translates to I take it? begins with an s and ends in a t :lol: Describes Citroen electrics rather well too.

I digress, sorry. Look at an earth in the circuit diagram (e.g. MC50 and MC11 from the instruments) and these can be found both on the harness diagram and on the location diagram. In our example above MC50 is Down at the very bottom of the dash under the ashtray and MC11 is on the earthing plate on the inner wing. The MMO4E Number by earth point MC50 for example in the harness and circuit diagrams is the number you will find printed on the wire itself.

On the harness diagram you will see numbers in a bold box (e.g. E162B) these refer to splices (i.e joints) in the loom. These are soldered and heat-shrunk and can go open-circuit if they get damp.

The harness diagram shows the looms the wires run though and have numbers such as 10PR. The location diagram shows there these looms run physically and in the case of 10PR it's the infamous loom that runs across the front crossmember and the cause of may electrical gremlins caused by coolant spilling on to it and corroding splices and wires.

Hope that helps?
Jim

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Post by KennyW »

Thanks Jim,

Yes the mud is clearing to a light silty deposit :lol:

As you are aware of my problem, are there any good auto sparks on the forum who could figure my problem.

Basically, supply is reaching the electrical parts in the fuel pump system but when I try and start the car, the supply disappears.

I have over riden this by a direct supply from the battery in conjuction with the normal supply through the double injection relay.

I remove the direct feed once engine is running as the normal feed is back on :!:

I believe there is a wiring issue some where but where :?

I suspect possibly one of the joints running to the double injection relay.

How reliable are the double relays on th MK2 TD's :?:

As according to Citroen the older models had a problem with relays but the newer ones where better?

Kenny
C5 x7 2.0 HDi 160 hp Estate exclusive, the newbie
Xantia 2.0 Hdi 90hp 1999 only 189,000 and rising!!!!!!! Moved on to a new home
C3 1.4 petrol (SWMBO)
Xantia TD 1.9 Mk 2 Estate LX 1998 model over 210,000 miles now and still rising!!!!!!!!!!!!! now deceased 17/12/2010.
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Post by CitroJim »

Ahh right, That smacks of a high resistance somewhere Kenny and I'll almost bet money it's in the 10PR loom :twisted:

If you can tell me exactly the point you see the voltage disappear, I'll work it out.

Double relays these days are normally very reliable but that's not to say. They're all the same right across the range. Visit a scrapper wearing your poachers coat and liberate one when nobody is looking; they're shockingly expensive.

Give me as much information as to where you see the voltage disappear and we'll give it a shot...
Jim

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Post by MikeT »

Have you checked the ignition switch Kenny? Sounds like the power to the fuel pump is missing only when cranking.
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Post by VertVega »

CitroJim wrote:...That smacks of a high resistance somewhere Kenny ...
This reminded me of the battery negative terminal wire corrosion in mine which caused ignition problems.
It was only one month I owned the car and it was disappointing to have such a problem :(
Corrosion was under the wire shield which was not visible at first look.
As a solution: new wire between battery <--> gear box ground point.

Could it be a similar case?

________________________________________

Edit: Kenny I've read your reply below and decided to write more.

In my case, large-diameter wire was corroded so badly that between copper threads it was filled with corrosion.
I cut off the shield and that corrosion stuff was something like dander :lol:
I'm not sure if this is a common problem. Terminal connectors were clean.
New wire still works (8 years!) without any problems 8-) I have taken care that it stays greased.
(Positive terminal wire is factory assembled.)
Last edited by VertVega on 30 Mar 2010, 19:41, edited 1 time in total.
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x 132

Post by KennyW »

Thanks for the replies,

Jim, I am slowly going through various points and the big loom you mentioned has still be checked but the waether has turned for the worst ( British Summer time has arrived) :x

I checked at the stop solenoid and it disappeared. I am going to check at the plug point driver sides in the inside of the wing near to indicator for voltages and work my way back.

I was going to take a direct supply from the ignition to relay to over come this and create a new joint at the old one for the relay.

Mike, I have 3 different ignition barrels and switches, including 2 new ones, so I don't think its the switch.

V, I will take the battery tyo gear box lead off and give it a good clean and grease it up.

Kenny
C5 x7 2.0 HDi 160 hp Estate exclusive, the newbie
Xantia 2.0 Hdi 90hp 1999 only 189,000 and rising!!!!!!! Moved on to a new home
C3 1.4 petrol (SWMBO)
Xantia TD 1.9 Mk 2 Estate LX 1998 model over 210,000 miles now and still rising!!!!!!!!!!!!! now deceased 17/12/2010.
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Xantia 1.9 TD estate
x 132

Post by KennyW »

Hi Jim,

The problem David Hallworth is having with his blower looks strangley related maybe to mine as I am going to check the ECC 1 splice joint.

I am going to test for supply from the grey igniton plug onwards.

I assume the 12V will be running at on and start postion so as to keep switch open on double relay to keep stop solenoid open to supply fuel to injectors.

Kenny
C5 x7 2.0 HDi 160 hp Estate exclusive, the newbie
Xantia 2.0 Hdi 90hp 1999 only 189,000 and rising!!!!!!! Moved on to a new home
C3 1.4 petrol (SWMBO)
Xantia TD 1.9 Mk 2 Estate LX 1998 model over 210,000 miles now and still rising!!!!!!!!!!!!! now deceased 17/12/2010.
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KennyW
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SWMBO C3 2012
Previous Citroen's
Xantia 2.0 90hp estate
Xantia 1.9 TD estate
x 132

Post by KennyW »

Hi All,

I have carried the following Voltage checks from the grey block connector at the ignition which into the fuse box.

At No2 Grey igniton switch connector 12 volts at ON position

Feed CC1 into fuse box 12V

Feed CC2 out of fuse box to double relay 12V

When key is turned to start motor

Grey No2 10V

CC1 & CC2 Volts

I thought to start the car 12 V would have to run to the relay to move the switch to the ON position to supply 12V's required at solenoid.

Have I missed anything, thoughts please.

Kenny

As an after thought, can anyone who has a Mk2 1.9 TD which is running check the voltages I have produced to see if my diagnosis is correct.
C5 x7 2.0 HDi 160 hp Estate exclusive, the newbie
Xantia 2.0 Hdi 90hp 1999 only 189,000 and rising!!!!!!! Moved on to a new home
C3 1.4 petrol (SWMBO)
Xantia TD 1.9 Mk 2 Estate LX 1998 model over 210,000 miles now and still rising!!!!!!!!!!!!! now deceased 17/12/2010.
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Post by CitroJim »

Kenny,

According to the diagram, CC and CC1/2 should be at nominal 12V in both the start and the run position of the ignition switch.

What voltage is present at BMF1 (Black Pin 1) on the ignition switch During starting?

If this is low too than something is dragging it down.

It's a strange one Kenny

:?
Jim

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