Heater Fan/Rear Demister (No Power To F21)

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Heater Fan/Rear Demister (No Power To F21)

Post by Steve_M »

Hi All

I've been trying to resolve my problem with the heater fan/rear demister not working on a Xantia MkII 2.0HDi. I am getting 0.3V on Fuse F21 and Pin 3 on the Blower Relay. I checked Fuse B in the engine bay and I get 12V both sides. I understand that the feed from Fuse B runs directly to F21, so I should be getting 12V there. Is that correct?

Have been reading many posts. The nearest answer is the last entry on this page:

http://www.frenchcarforum.co.uk/forum/v ... 21#p218130

Any hints on how/where I might resolve this? Any work-around?

Many thanks

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Re: Heater Fan/Rear Demister (No Power To F21)

Post by citroenxm »

My guess is, and Ive had this on a T reg S2 is that theres a break in the feed from the engine fuse box to the in car fuse box.

the harness leaves the car through a massive multi was plug in the drivers corner of the bulkhead, and passes then through to between the inner wing and outer wing parts over the top of the arch linner. It then drops down and goes along the front of the cars lower edge below the radiator, bumper side and up and through the pasenger side to the right of the battery and then goes to the appropiate areas in the engine fuse box feed supply areas...
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Re: Heater Fan/Rear Demister (No Power To F21)

Post by RichardW »

Haven't got the diag to hand - is it the power side or the switching side of the relay (presume you are talking the relay above the throttle pedal?). If the switching side, mine did this - I just ran in a new supply from the switched side of the blower part of the ignition switch under the column shrouds - been like this nearly 5 years, and works no problem at all!
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Re: Heater Fan/Rear Demister (No Power To F21)

Post by Peter.N. »

I would agree with Richard, I have had several similar problems over the years and the only practical solution is to run a separate lead, sometimes using a relay if its a headlight failure for instance.