Peug:306 Fan Drains Battery

[RichardF]

Hi,

I have a 306 xsi 2.0 (3dr).

I've had this problem intermittant with the car for a couple of years now and it seems (at some expense) that no one is able to fix the problem. I wanted to post here to see if anyone has experienced the problem or could hint at possible solutions....

Heres the problem:

The radiator fan turns itself on (despite no key in ignition) and the fan runs for ever until the battery is flat. This usually happens thru the night so when i get to my car in the morning im greeted with a flat battery! This doesnt happen all the time but i would say it happens more frequently during the autumn months. Sometimes if I get to it in time and i turn the key (with or without starting the engine) the fan clicks off, othertimes it just continues.

My theory is that the changes in external temperate is triggering of some thermostat which tricks the car into thinking it needs the fan on.

I have taken this to peugeot several times and having run their diagnostic equipment it reveals no faults. As you can imagine its difficult to take to a garage since the battery is flat when it happens, and its impossible get a booking (and at the same time predict when the problem appears).

Thanks.
Rich.

 

[keyplayer]

Sounds like a ropey thermo switch to me, although a mystery why the dealer shouldn't be able to diagnose. Don't know this model but unit is usually found on the bottom of the radiator. Check for continuity across the terminals when cold (and when problem occurs) and if cont. exists replace unit. If unit functioning ok then you've probably got an intermittent short on the wiring. Take care replacing unit, radiators both pricey and delicate!!