Xantia cooling fan temp sensor location

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liam
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Xantia cooling fan temp sensor location

Post by liam »

Help! I can't find the cooling fan temperature sensor on my 1996 1.8 16v Xantia. I need to replace it as the fan stays on continuously, including when the engine's switched off. I thought the switch/sensor would be on the radiator, but can only find a blanking plate on it. I think I'm right in saying that none of the 3 temperature sensors on the thermostat housing are related to the fan either. So where is it?!! Please help!
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Post by Peter.N. »

I think that it is one of those on the thermostat housing, I'm sure someone will put me right if it isn't. If you have tried unplugging them all and it doesn't stop, it could be a relay that has stuck closed
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Clogzz
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Re: Xantia cooling fan temp sensor location

Post by Clogzz »

liam wrote:I think I'm right in saying that none of the 3 temperature sensors on the thermostat housing are related to the fan.
Yes, they are.
Does the car have air conditioning ?
If yes, then it has a 'Bitron' to control the fans.
The Bitron is a metal box about the size of a cigarette packet and lives in the fuse box under the bonnet, and its connectors are the cause of most fan troubles.
What I did was to clean the Bitron terminals with the rough end of a piece of broken metals hacksaw blade, then swept out the scraps of solder with a paintbrush, and it's been good since.

Here is the map:

http://www.frenchcarforum.co.uk/forum/v ... hp?t=17012

If no air conditioning, then it's a relay fault as per Peter's post above, and Hello to you, Peter. :)
Last edited by Clogzz on 28 Nov 2005, 12:19, edited 1 time in total.
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Post by RichardW »

Assuming the car's got aircon, the it will be on the thermostat housing. It should be the brown sensor, and it will probably have 2 wires on it rather than just the one of the other sensors. If the sensor is unplugged or goes open circuit, then the Bitron fan controller will switch the fans on at high speed - even if the ignition is off. I imagine there will be fuse for the fans, so you can pull this out to stop them running while you fault find. It may be that the sensor is goosed, or the wire is broken, or the Bitron itself is faulty - the location of this varies, but it may be close to the LH headlight.

At least the fans work :D
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Post by Clogzz »

RichardW wrote:or the Bitron itself is faulty - the location of this varies, but it may be close to the LH headlight.
I think, and hope, that on all the petrol models it's inside the fuse box.
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liam
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Post by liam »

Thanks very much everyone! The car doesn't have air con, and when I pulled the plug off the brown sensor onn the thermostat housing, the fan stayed on but there were no effects at all. The top sensor controls the temp gauge and the bottom one the fast idle, but like I said, the middle one had no effect. I suppose, with no air con, this points to a stuck relay then?
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Post by Clogzz »

liam wrote:this points to a stuck relay then?
Probably yes, but pulling the wire off the brown sensor will in itself cause the fans to spin.
So, besides relay faults, the sensor, or more likely, its wiring may be open.
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