Xantia ABS ECU pin numbers

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higgy
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Xantia ABS ECU pin numbers

Post by higgy » 01 Sep 2002, 22:01

Here are the pin numbers on my Xantia td abs ecu (1994).
1 & 6 f.o.s. sensor
15 & 30 f.n.s. sensor
29 & 31 r.o.s. sensor
28 & 19 r.n.s. sensor
11 earth
13 to abs relay terminal 30
16 earth
22 feed from brake pedal
24 earth
25 diagnostic socket
27 diagnostic socket
32 abs relay terminal 85
33 abs relay terminal 86 & 12v feed from fuse 6
37 diagnostic socket
The abs relay is located on the fuse box mounting bracket next to the battery and is a 6 terminal green relay.
I have spent half of today tracing the wiring on my car but it still hasn't helped me solve my problem.Possibly it might be the abs relay,if not its going to be a new ecu.Iv'e opened up the ecu today as well but there isn't really alot that can be done in there,the circuits are printed on a plastic film that is glued onto the inside of the ecu casing.I found that the peugeot 406 haynes manuals abs wiring diagram was of some use in trying to work out what went where.
Why cant they (haynes) give a diagram in the xantia manual.
Hope this helps anyone trying to sort out their abs light.
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David Goddard
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Post by David Goddard » 02 Sep 2002, 00:17

Brilliant info!
I read some where (an XM article, I think) that an ellusive fault was traced to a bad soldered joint in the ECU module. One of the multi-pins to the pcb. When you took yours apart, can you get to any of the connector pins to check that they are OK. (As you can tell I have a problem - the sensors are OK. I checked the green relay - that works OK and its relay contacts are sound - no more that 0.5 Ohm).
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higgy
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Joined: 21 Apr 2002, 03:19
Location: United Kingdom
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Post by higgy » 03 Sep 2002, 03:13

Yes you can get to the pins on the circuit board but thats about all.
Be very carefull opening it up, if you try to lever the lid off the circuit board is very close to the edge.I can put my abs light out by manualy changing the contacts on the relay but this doesn't make the abs work, I think the ecu should change the supply to the relay to earth but for some reason it isn't, after a day to think about it im going for an ecu.
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skysurfer
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Post by skysurfer » 30 Sep 2002, 16:06

Can you get the case off the ECU and put it back on <b>without anyone being able to tell you've been in there</b>? (In case it still needs <i>professional</i> repair later).
I don't understand why <i>"there isn't really alot that can be done in there"</i> when the case is off.
Is the tracking & soldering on the side of the board that's glued to the case? Is the flexible circuit board too delicate to peel off from the glue?
I would have thought that it would all be done with surface mount components and they would all be on the side of the flexible board that you can get at?
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higgy
Posts: 36
Joined: 21 Apr 2002, 03:19
Location: United Kingdom
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Post by higgy » 01 Oct 2002, 01:50

I don't think it's possible to get the case off without some damage.
It's made of cast aluminium and it's crimped on so when you try to un-crimp it the casing snaps.Also the casing is glued on with some kind of mastic compound.
The glue holding the circuit board is very strong,I tried to pull it off but I was worried about damaging it. The circuit board is also covered with some kind of laquer which is very thick. By all means have a try at it yourself but be warned. Im sure I need a new (secondhand) ecu so at the weekend I'll take it off again an have another go at dismantling it, I've got nothing to lose now!
Best of luck if you decide to have a try.
Edited by - alans on 30 Sep 2002 22:29:47
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