Peugeot 405 Diesel (1988 - 1996) - 1996 1.9 Cooling Fan

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Thu 11 Sep 2008 18:35
1996 1.9 Cooling Fan - jonlucpicard
One of the cooling fans on my 1996 405 TD is running constantly with the ignition on. The guy i bought from said his mechanic rewired it like that as the previous engine had overheated.
I have checked the 3 relays and all the wiring is intact and doesn't look like it's been touched.
I have read on the internet that it could be the bitron sensor for the air con.
Where is this located?
How can i test it?
How much is a new one?
Anyone got any other suggestions?

Cheers
Jon
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Thu 11 Sep 2008 19:18
1996 1.9 Cooling Fan - Screwloose
Jon

IIRC it's behind the left-hand headlamp - or possibly in the wheelarch. Fairly big money in it's day - not easily testable.

Check that the [brown?] plug to the 3 temp sensors on the water elbow isn't off?
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Thu 11 Sep 2008 22:01
1996 1.9 Cooling Fan - jonlucpicard
Would a faulty bitron cause only one fan to run or both?
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Thu 11 Sep 2008 22:09
1996 1.9 Cooling Fan - Screwloose

IIRC it put the fans in series for slow speed and parallel for high; so if only one is working, there's something odd afoot.

The whole system redefined "Heath Robinson lash-up," so good luck trying to make head or tail of it.
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Fri 12 Sep 2008 00:19
1996 1.9 Cooling Fan - Fullchat
Its a while since I did it but so the facts may not quite right but here goes: The wiring for the cooling fans disappears under the bonnet slam panel quite low down. I remember having to remove the front bumper for access. Where the wires join the main loom you have to split the loom and find the earth wire and follow it to where it is soldered to other earths (its not far). I found the earth joint all corroded. It was a matter of cleaning and re soldering and all was well.
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Sat 13 Sep 2008 18:25
1996 1.9 Cooling Fan - jonlucpicard
Ordered a new air con temp sensor. See if that sorts it.
Theres no sign of any wiring being tampered with and it all looks in good condition.
Also just noticed that the STOP sign is on when the engine is running, didn't notice it before as the car is currently parked up and not being used. Will this be related the fan problem?
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Fri 25 Sep 2009 09:57
1996 1.9 Cooling Fan - parchwba
Help! I got a similar problem. The drivers side fan is constntly on even when the key isn't in the ignition. jonlucpicard did you get it fixed, please tell me if and how???
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