heater fan and rear-window demister failed

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D.Slatford
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heater fan and rear-window demister failed

Post by D.Slatford »

The last couple of days, the first electrical problems have reared their ugly heads on my 'new' Xantia :(
On two journeys now, the heater fan refuses to work, and at the same time, the rear window demister won't switch on. Or if it does, it'll only be for a second, then switch right off. The fuses for each are fine. Now the days are getting colder, and I'm driving more, this is a huge concern.
There's presumably power to the climate control box under the dash, as I can hear the flaps being moved across the heater matrix when I adjust the temperature control. Just no fan, and no rear demister. Anyone know the common link?
RichardW
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Post by RichardW »

Common link is the ignition switch [}:)]
It carries all the current for the heater fan and the heated rear window and is not man enough for the job, and the contacts burn out. What you need to do is fit a relay instead. There should be enough contact left to switch the relay, though. I think if you take the lower steering column shroud off, you will find a brown plug with 2 heavy duty (yellow?) wires going into it. You need to separate this plug and put a relay in its place, using the ignition switch to switch only the low current side of the relay. It should be pretty straightforward (as long as you can identify the correct plug!).
In the mean time, ensure the blower and HRW are switched off until the engine is running, and switch them off before you shut down, as this will reduce any further damage to the contacts.
PeterMann
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Post by PeterMann »

If you would like circuit diagram and photos and a description of the procedure to install a shunt relay as described by RichardW, email a request to nicolesv@optusnet.com.au
D.Slatford
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Joined: 13 Nov 2001, 06:06
Location: Wakefield, United Kingdom
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Post by D.Slatford »

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by PeterMann</i>

If you would like circuit diagram and photos and a description of the procedure to install a shunt relay as described by RichardW, email a request to nicolesv@optusnet.com.au
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
Tried to send a mail, but bounced, no such user.
I'd appreciate the diagram. dan@foxhosts.co.uk
Waxee
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Post by Waxee »

I have the exact same symptoms/problem with my VSX and have spent the last week trawling this fantastic forum to discover that it is a common known problem.(that comforting in itself) You will also find mention of checking some electrical contacts situated under the battery. I haven't got that far yet because I needed to find out the radio code before disconnecting the battery. Also I read that before you work on the ignition switch you will need to remove the steering wheel, hence disconnecting the airbag (this worried me a bit, I don't like things that go bang)It appears Citroen change specs and build procedures on a regular basis and thus not all repair/fault rectification methods will be the same per model year.
So as yet I have not yet got to work on the car, if you do get any circuit diagrams or get yours sorted before mine I would appreciate your input. Good Luck
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