3 way fan switching

[AndyLala]

£10 says once you get the buzzer working, two weeks later you'll disconnect it...

[Vagrant No2]

£10 says once you get the buzzer working, two weeks later you'll disconnect it...

Easy £10 in my pocket . Runner sits outside the house for 3-4 weeks at a time
Buzzer would only come on if the fan is switched off , which would be only if I wanted to go through deep water , which in a petrol motor is rare .

[da SLUG man]

£10 says once you get the buzzer working, two weeks later you'll disconnect it...

two weeks!!

nah, 2 hrs!

[MattF]

So I now have position 1 : fan controlled by thermo switch , position 2 : fan over ride thermo switch , fan on and yellow warning light on, position 3 : fan off and red warning light on .
Might fit a buzzer for position 3 aswell .
Dont really know who it works but does !!!

Lotus parts fixed my Runner twice now

And the relay to which the off light is connected is wired how?
Also, this three way switch. Does it have a common contact which
goes to the fan, and then thermo/+12V/and nothing connected to
the other contacts, or is it a three way, separate set of contacts for
each position switch? Just trying to get an idea of how you have
this setup wired.

[Vagrant No2]

And the relay to which the off light is connected is wired how?
Also, this three way switch. Does it have a common contact which
goes to the fan, and then thermo/+12V/and nothing connected to
the other contacts, or is it a three way, separate set of contacts for
each position switch? Just trying to get an idea of how you have
this setup wired.

The original switch I bought had 6 contacts on it . I assumed they made contact in pairs as they were switched , this is where I got stuck as they did not . The common(+) is in the middle contacts and the contact either up or down , hence the on/off/on switch . This gave me the prob of the OFF light staying on as I needed a positive feed to switch it off in the thermo switch position .
The switch I have used , is as I said , an old headlight switch and without taking it all apart again can not remember how I got the switching .
I will try and scan a diagram if I can tommorow .

[MattF]

Been trying to find a schematic of the fan circuit. No luck so far.

Quick question:
Is the thermostat connected to a changeover relay for on/off
switching of the fan in the standard factory setup? Thinking back
to one of the posts last week, I think I may have misinterpreted
how the default circuit works. Does disconnecting the lead to the
thermostat switch the fan on?

[Vagrant No2]

Been trying to find a schematic of the fan circuit. No luck so far.

Quick question:
Is the thermostat connected to a changeover relay for on/off
switching of the fan in the standard factory setup? Thinking back
to one of the posts last week, I think I may have misinterpreted
how the default circuit works. Does disconnecting the lead to the
thermostat switch the fan on?

Matt , all my stuff is non standard as the 1st gen didnt have an electric coolant fan . I have ditched the engine coolant fan as the fixed one was noisey and the thermo viscous one was useless .
Basic circuit is a 12v feed from battery to a relay and then to fan and then earth . The relay is positive controlled via the switch feed from ignition. It has a position to turn the fan on via the thermo switch (kit off ebay £32 inc p&p) to the relay . The overide is run by the switch to the closed side of the thermo switch , therefore bypassing it , also a light to show it is on (also illuminates when fan on thermo switch) .
The off position has a bulb wired to the overide side of the relay which makes a circuit via the relay but will not close the contacts as the overide bulb draws the current away from contacts . This bulb goes out when the feed to relay is made positive due to the relay going from negative to positive (same principal as alternator warning light) .I was lucky that the headlight switch I used also had a feed in the thermo switch position which I used to put light out in thermo position which was my prob I had .
Sounds complicated but I only got stuck with 1 bit .

[MattF]

So you've got the off light on thermo setting sorted now then? My
brain just refuses to kick in correctly today.

[Vagrant No2]

Matt
Here is the diagram of the wiring as best I remember . It does not show the extra link to the OFF light which was inside the headlamp switch to keep the OFF light off in thermo switch position .

[MattF]

Matt
Here is the diagram of the wiring as best I remember . It does not show the extra link to the OFF light which was inside the headlamp switch to keep the OFF light off in thermo switch position .

Nice job. Must be a weird switch, to have caused that off light problem.
Very nice diagram, BTW. Curiosity well piqued now, was the off light on
constantly in thermo mode? Also, does the override light come on when
the thermostat kicks in?

[Vagrant No2]

Nice job. Must be a weird switch, to have caused that off light problem.
Very nice diagram, BTW. Curiosity well piqued now, was the off light on
constantly in thermo mode? Also, does the override light come on when
the thermostat kicks in?

Being a headlamp switch it had different contacts making in different positions , I think I used it in reverse to wot a headlamp switch would do ie turn things off instead of on !
No the off light was off in overide position as the overide changes the feed to the relay to positive from negative .
Yes the overide light comes on with the fan when the thermo switch kicks in .

[MattF]

Yes the overide light comes on with the fan when the thermo switch kicks in .

Intentionally?

[Vagrant No2]

Intentionally?

Err , no

[Apache]

Do you have the 'off' light, and the override light in series? Looking at the diagram, they'd both be on but dim when you've got the fan turned off, or are your colours indicating different switch poles?

[Vagrant No2]

Do you have the 'off' light, and the override light in series? Looking at the diagram, they'd both be on but dim when you've got the fan turned off, or are your colours indicating different switch poles?

The bulbs only share 1 common terminal .The overide light is in parrell to the relay and goes to earth like the relay . The off light uses a positive feed that is live on its own (which was the prob I had to find) and earths via the relay positive but uses the relay positive as a negative when the relay is off . This can sometimes trip the relay , but the overide bulb takes the initial surge from the relay to stop it making contact and the overide bulb will not illuminate .
If you follow that , you are better then me , I knew the theory but in practice it gave me a headache , a headache that lasted 3 days !! I was supposed to finish paint strippering the front door but told Tam the fumes would make my headache worse