Morris Minor Owners Club

Hi need a bit of help with my heater wiring, ive got all the wiring out from behind the dash, clock and switches, heater all removed, and now cannot remember how the heater is wired up, ive got a green/yellow wire coming from the switch, and a white wire from the heater motor area, question is where do they connect to, my book does not mention heater at all, thanks in advance, regards steve

Steve
It sounds as though things are in a bit in a muddle.
Assuming nobody has tampered with/ altered the wiring in any way. the wires you refer to are not connected to the heater.

White wire is the Ignition circuit.
Green/ yellow tracer should be either the OIl filter warning light
or the Oil pressure warning light
The heater should have a Green feed wire from the switch and the heater should have a Black earth wire.
( Workshop Manual Issue 2 Plate N.44 ) Wiring diagram ( Models with Separate Flashing Equipment ).
Stick a label on every wire, as you identify them, double check again and then connect to the relevant switch/ connector.
Bob

On my Mog, I have the same situation -- Mog's got the earlier round heater. Green/yellow is the power input, coming from the oil pressure warning light. White is earth, for some reason, and it earths direct to control box "E". When doing Mog's wiring, I replaced the white wire with black, for clarity's sake. Does your Minor have the round heater or the boxy one?

On my 62 with a round heater I have a white and a black wire. Black went to earth and the white went to a green directly from the fuse box.

Thanks Beero for reminding me -- I should add -- no guarantee at all that Mog's wiring is unmodified!

thanks for the info, ive checked a bit further and have now found that the green/yellow was originaly connected to the back of the wiper switch, but still no luck with regards the white, i willl have to get under the dash again to try and trace it, thanks for all the help so far. regards steve

The heater should have short lengths of black wire and white wire connected to bullet connectors. The switch is part of the heater which makes the wiring diagram confusing. However all you need to do is connnect one wire to an earth wire and the other to a green ignition switched wire and check that the heater is blowing in the correct direction.

Mike,
On the later heater you cannot change the direction of rotation. There is an arrow on the fan and the motor turns exactly in the opposite direction no matter what the polarity is. I have bench tested it several times.
Regards
Declan

thanks for that, ive tried to get the heater running on the bench with no luck, ( am i being stupid) i connected the green / yellow wire to a battery + and the white to the - , result , nothing working, i had a test light fitted in the circuit, which did go on and off with the switch being opperated. the heater was working ok in the car before being removed, is the heater earthed via its mountings to the body?? regards steve

Steve,
No, you are not being stupid-quite the opposite. It should run on the bench via a battery. Maybe the motor brushes are worn or a broken connection. Open it up and have a look inside and expect to find allsorts in there.
Regards
Declan

Declan thanks for that, i guess its back to the bench with it.

regards steve

There should be a black and a white wire connnected to the heater, these are the wires that you connect to the battery to test. You could also check that the on/off switch on the heater is still connected.

thanks again for all the help, ive now got the heater running on the bench, it runs in opersite dirrection to the arrow on casing, as was sugested earlier on, and polarity does not seem to matter, just power and earth either way. many thanks, regards steve