Heater wiring

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Propshaft
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Heater wiring

Post by Propshaft »

Just fitting a new loom to my 69 traveller need confirmation the green wire from the heater switch does it go to the stabaliser if so which side . Thanks
Propshaft
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Re: Heater wiring

Post by Propshaft »

Sorry for wasting your time just found the answer in previous comments
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Bill_qaz
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Re: Heater wiring

Post by Bill_qaz »

Propshaft wrote: Fri Mar 13, 2026 7:36 am Just fitting a new loom to my 69 traveller need confirmation the green wire from the heater switch does it go to the stabaliser if so which side . Thanks
This may help
Screenshot_20240319-133045_Samsung Internet.jpg
Screenshot_20240319-133045_Samsung Internet.jpg (181.46 KiB) Viewed 34429 times
Last edited by Bill_qaz on Fri Mar 13, 2026 10:02 am, edited 1 time in total.
Regards Bill
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svenedin
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Re: Heater wiring 1969 late car

Post by svenedin »

The green wire is an oddity. It connects to the live side of the wiper switch. It only uses that as a convenient place to pick up a live when ignition on connection. The black (earth) wire can go to any convenient earthing point. Note: there are 2 different designs of motor used in the later heaters, both made by Smiths and they look identical from outside. One type has permanent magnets and will turn backwards if the car's polarity is changed from positive to negative earth. The other type has windings and no permanent magnets and it turns the same way regardless of polarity. The centrifugal blower impeller (fan) works much less efficiently turning the wrong way and the already less than wonderful air flow will be reduced. If unsure (and the car has been changed to negative earth) then the heater wires need to be changed round to: black to live side of heater switch; green to an earthing point.

Stephen.
1969 1098cc Convertible “Xavier” which I have owned since 1989.

Stephen
Propshaft
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Re: Heater wiring

Post by Propshaft »

Thank you both for your detailed reply’s
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