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Tony
10-07-2013, 00:24
Hello Williams Lovers,

Im currently get a williams through its MoT after its been sitting "broken" for 4 or so years.

Several problems but one of them is a bit baffling to me as ive never come across it.

The cooling fan does not come on when the car gets hot and the ignition is on (engine off or on) but as soon as you turn the ignition off the fan comes on, it will turn off again if the ignition is turned on again. The fan will continue to run until the battery dies if you turn it off and walk away, so i currently have to make sure i let it cool then turn the ignition on and off again.

I assume there is a cut off switch/relay that cuts power to the fan when the ignition is turned off and i believe it is this that is broken, and working in reverse. Does such a switch exist? Where is it?

Where can i find a wiring diagram? is it the same as the valver?

Any other ideas?

any help much appreciated.

Cheers

Wobba
10-07-2013, 10:07
http://williamsclio.co.uk/forum/showthread.php?3129-Cooling-fan-trouble&highlight=fan+kicks

:)

Might help.

Tony
10-07-2013, 12:36
Thanks, in that thread they are talking about a switch do they mean the temperature switch on the side of the radiator? or another switch?

Is there a wiring diagram anywhere for a williams? or even a manual (like haynes)?

cliokiz
10-07-2013, 14:18
With ignition off, the fan is controlled by a switch on the thermostat housing (as well as the electric auxiliary water pump), with the ignition on, it is controlled by the fan switch on the drivers side of the radiator.

I bet the wiring has broken off the plug which is why it isn't working. To test, bridge the red/yellow wires leading to that plug and it should activate (or bridge the terminals in the plug)

If it doesn't work when you do that, the issue may be the relay in the fuse box behind the passenger side headlight, although i'm going to guess both sensors are wired to the same relay so if one works they both should.

Tony
10-07-2013, 14:33
I thought the one in the thermostat housing is the temperature sensor that controls the gauge on the dash, seems strange to have 2 switches?

also shouldnt the fan turn off when the ignition is off?

16v_paddy
10-07-2013, 18:37
I thought the one in the thermostat housing is the temperature sensor that controls the gauge on the dash, seems strange to have 2 switches?

also shouldnt the fan turn off when the ignition is off?

There's 3 sensors in the thermostat housing 1 for the ecu, 1 for the gauge on the dash & 1 for the fan. Mine is doing the same thing now despite fitting a new sensor in the rad :evil:
The fan is supposed to work with the ignition off, you'll notice newer cars have a warning sticker on them saying the fan can start at any time, older cars like these don't have them as people weren't as stupid or as likely to sue if they had their tongue cut off by the fan when these cars were new :winkey:

Vandella
10-07-2013, 18:38
no haynes manual.. although i pressume it would be fairly similar to the 1.8 16v covered in the haynes manual for mk1 clio.. or i can sort a pdf version of the manual that should come with the cars docs n books, if u pm me ur email

Tony
10-07-2013, 22:40
I think i have all of the manuals that came with the car, is there a wiring diagram in there?

Oh ok, so i need to check the radiator switch with ignition on and the thermostat switch with ignition off yes?