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Old 14th August 2018, 22:41   #11
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Hi T-cut, no this is when everything is off no key in the ignition, I can only stop it by disconnecting the battery, then it starts again when I reconnect the battery - no key in the ignition.
Yes, I should read the posts better. It does sound like a faulty relay. The fan is permanently connected to battery power and all switching is done on the earth return side. So, a faulty relay or its solenoid supply can make it 'on' all the time.
You said the relays are OK, but how did you test them? Get new from Halfords and try swapping them.

Is your fan a 2-speed or the earlier 3-speed? The resistor system is the later 2-speed.


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Old 15th August 2018, 07:18   #12
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Hi checked .... the relay associated with the fan and all is ok ...
Steve; the relay in the engine compartment fusebox labelled with fan blades is for the heater blower motor not the radiator fan! The radiator fan relays (there are more than one) are in a control box which can only be accessed by removing the front bumper. This is why I suggested the tests in post number 4 to try to avoid unnecessary dismantling.

So, can you remove fuse no. 4 (15 amps) in the underbonnet fuse box, start the engine with the heating in ‘Econ’ mode and observe whether the radiator fan still runs continuously. If it doesn’t, the relays are being triggered by a short circuit, most likely in the wiring loom. If the fan still runs, suspect a relay or damaged fan wiring and the bumper will have to be removed for further investigation. I don’t recommend buying anything until we have a reliable diagnosis since your fault is unusual on a petrol-engined car.

Simon
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Old 15th August 2018, 11:30   #13
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Ok thanks guys, will be Bank holiday W/E now before I can take the front off. If I have to do that I may as well change the resistor to the gold one as well. The car is a 12/2004 but registered in 07.
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Old 15th August 2018, 11:39   #14
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... will be Bank holiday W/E now before I can take the front off.
Steve; you only have to open the bonnet to do the fuse 4 removal test. I recommend that you do that straight away. Depending on the result, you may not have to remove the bumper.

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Old 26th August 2018, 10:51   #15
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As if by magic,I reconnected the battery yesterday and the engine fan seems to have sorted itself out...! It was a fortnight without use or the battery being connected. I have no idea why. We used the car a couple of times yesterday and the fan stayed off.
Thanks for all the previous advice.
Steve
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