Sounds to me like the switch

There are two wires from the switch
green/yellow pos 1
green pos 2


This suggests that "green/yellow pos 1" is live as soon as the ignition is turned on as well as when the switch is actually in Pos 1.

Check if it is also live when the switch is in Pos 2.

Try temporarily swapping out the switch, even just to an on/off switch. If the heater doesn't come on when the temporary switch is off but does when it is switched on then it is definitely your switch

WCA

No power to either of the switch terminals with the ignition on?
I think the Haynes diagram may be wrong.
with power going directly to the motor on one side and an earth wire coming from the heater rheostat the motor is going to run as soon as the ignition is turned on ' if I disconnect the earth the motor stops.
if I disconnect the power the motor stops.
I have temporally put a on/off switch on the power lead :hurt: until I can figure it out

wops I'm wrong there is power to switch no 2 with the ignition on

I am guessing it is okay to have power to the switch with the ignition on but the switch should not send the power to the heater unless in position 1 or 2.

Probably not much help and I am off to sort out my own electrical gremlins now.

I just borrowed a prospero's garage diagram and it's different wired up as per prospero's and I have a two speed blower but it's still on slow speed when the ignition is turned on so I'll wire in a on/off switch! The workshop manual diagram is wrong???????

If the heater motor runs with the switch at 0, either the switch is stuffed or there's another feed bypassing it.

Probably the switch I've just blown my last spare fuse so I am giving up for the day

No joy with the heater blower so I'll leave the inline switch in place' the flasher relay arrived today but will only work if I fiddle with the switch so both were at fault. Anyone got a indicator switch assembly for a 1500 spitfire? Ho and then my soldering iron died so I've given up for the day again.

I've had a much better day today with the wiring other than the indicator switch and the blower all circuits are now working properly (let there be light) even the overdrive solenoid is working as it should the H manual diagram for it was totally wrong again (prospero's garage rule ok)
I am a much happier camper today.

A bit more progress today all the wiring circuits apart from the indicators (new switch needed) are now working
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So I decided to go for a start up filled up the fluids ? nothing no spark I have a Accuspark contactless system installed so I spent ages checking everything then decider to re-read the instructions apparently there can be a problem with the trigger being to low this can be checked by raising the trigger by 2mm and testing for a spark there was so I put it all back together and she fired up on the second attempt yahoo
I phoned Accuspark and they are sending me a upgraded rotor arm with the trigger built in free of charge nice one Accuspark
[IMG]http://i410.photobucket.com/albums/p...k/DSCF0710.jpg[/IMG]
I thought I was on the home straight until I noticed the rad was peeing all over the floor and the carbs are leaking from the float bowls and the needle valves
[IMG]http://i410.photobucket.com/albums/p...k/DSCF0711.jpg[/IMG]
[IMG]http://i410.photobucket.com/albums/p...k/DSCF0712.jpg[/IMG]
[IMG]http://i410.photobucket.com/albums/p...k/DSCF0714.jpg[/IMG]
Oh the joys of motoring new rad about £200 ish carb rebuild kit £90 ish I'll have to start saving all over again I emptied the piggy bank last week.:wacko:

Oh the joys of motoring new rad about £200 ish carb rebuild kit £90 ish I'll have to start saving all over again I emptied the piggy bank last week.

If it has tyres or tits it will cost you money and leave you crying...

very true I think I have some brake fluid so I'll bleed the brakes next that shouldn't cost anything???? famous last words!

And they both leak when they are f@@ked

:-()

I'm getting nervous now!

A small mount of progress this week the rad has been taken for a re-core. In the meantime I decided to turn the car around a couple of friends came over to give me a hand whilst pushing it out of the garage there was a horrible clunking/crunching sound? lots of speculation as to the cause!! to cut a long story short I started stripping down the rear axle took off the off side rear drum and found a retaining spring floating around in the drum no springs missing so some stupid dork left it in there when he was re-building them last time doh !!!!! I managed to bleed the brakes with the help of her indoors no leaks something went right at last.
I have started to make a cover for the heater as it's in the passenger foot well not finished yet but you get the idea
[IMG[http://i410.photobucket.com/albums/p...k/DSCF0722.jpg]/IMG]

Had my re-cored rad back yesterday fitted it this morning and filled it up all looking fine until I heard the gentle drip drip of water! after much searching I found the leak coming from water pump union the one that runs under the carbs so I am currently trying to get the pipe of without removing the carbs Agghhhh fiddly as h#!!

Well I fixed one leek and found another(I don't think this cooling system loves me?) I have a MG type dual gauge water and oil but the water sender nut won't tighten on to the sender there must be a fix for it as other people have used them in triumph based cars anyone know how it's done????

we all feel for you matey! but you'll get there, it's looking really good!

Some of these fittings use BSP threads so a plumbers' merchant may be of more help than Halfrauds.

The nut actually fits but it doesn't tighten down on the sender it seems as if there should be a seating in the pump housing for it???