Another first time BX failure

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Another first time BX failure

Post by Jaba »

I have been investigating why the rear screen heater was inop. First thing was the soldered on contacts on both sides had come adrift, easy to fix I hope. Then I noted there was no 12v on either side and the switch did not illuminate when clicked on.
So I had to delve into the voltage distribution board behind the glove box. Uughh what a mess of spaghetti. Eventually I found that although the HRW relay was working the 12v in pin had no voltage sometimes. Further, I found that if I pressed on the cover underneath the relay pin then the 12v would appear. So that's a failed board, never had to change one of those before.
Looks like a fun job, 5 rows of up to 6 connectors to unplug and replug under the dashboard and it cannot be done 1 plug at a time as there is no space. Fortunately the board has a colour coding system to help place them all back in the right place. I guess its unplug from the front and replug from the back. Heres a few photos in case you are not familiar with this particular piece of BX design sophistication. The first one is of my replacement board.

DSC03649 (Large).JPG

And here are shots of the viscera with the aforementioned colour coding dots visible

DSC03652 (Large).JPG
The Joy of BX with just one Citroën BX to my name now. Will I sing Bye Bye to my GTI or will it be Till death us do part.

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Re: Another first time BX failure

Post by Rosieuk »

I think the quote goes something like:

"rather you than me..".

If you can split the grey cover casing it might be possible to find a dry solder joint or something like that. When you say you press the casing is that on the front side (ie where everything plugs in) or the back of the whole thing (ie firewall side). If it's the latter the connector might be a bit slack and a couple of dabs of solder on that particular connector (on the relay) might fix it by making a tighter connection because of a thicker pin.. Just a suggestion.

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Re: Another first time BX failure

Post by KevR »

I had a similar problem when trying to track down why my radiator fans didn't work - turned out to be no 12V to the relevant relay on the board. In that case I just added a switched feed to the appropriate outgoing wire. Took me bloody ages to track it down in the first place though.
1990 BX TZD Estate ('the grey one', 1991 BX TZD Estate ('the white one'), 1982 2CV6 Charleston (in bits), 1972 AZU Serie B (2CV van), 1974 HY72 Camper, 1990 Land Rover 110 diesel LWB, 1957 Mobylette AV76, 1992 Ducati 400SS, 1966 VW Beetle, 1990 Mazda MX-5, 1996 Peugeot 106D, 1974 JCB 2D MkII, 1997 BMW R1100RS, 1987 Suzuki GSX-R1100, 1978 Honda CX500A, 1965 Motobecane Cady, 1988 Honda Bros/Africa Twin, 1963 Massey Ferguson 825, and a lot of bicycles!