Help with Heater / Blower Switch Wiring

[Dazza the Stag]

Only a couple of jobs to do to finally get the car back together following the heater motor replacement. I had the heater motor tested before i put everything back together but now I seem to have an issue with the switch.

When the pull switch is in the off position or position 1 then the fan is on speed 2 and when the pull switch is pulled out fully the fan is on speed 1

If I swap the green/yellow wire with the green/grey on the back of the switch then when the pull switch is off i get speed 1 and when its pulled to position 1 and 2 its on speed 2 !!

Confusing or what - so its never actually off

Is there a simply explanation for this - I’m guessing its at the switch end - if its at the motor end then its staying that way as I’m not stripping it down again lol

Any ideas ? Is there just the 3 wires going to the back of that switch - there are a couple more terminals at the back not being used but i cant see any spare wires

Dazza

[DZP]

Hi Dazza,

Hopefully, this will simply be a short in the switch.
The switch either puts:-
12v via a dropper resistor to the motor via the GY coloured wire for low speed.
12v directly to the motor via the GS coloured wire for high speed.

Switch pin1 = Purple
Switch pin4= Green/Yellow
Switch pin8= Green/Slate

Remove all the wires from the heater switch.
Does the fan stop, then it is a short in the switch?
Does the fan still run, if so, you have a short in the loom somewhere. You could disconnect the plug leading up to the heater motor to debug further?

I replaced my heater switch when I reconditioning the heater assembly, but I must say the new switch was of very poor manufacture, as was the replacement dash back-light rheostat switch.

Den

[bullstarz]

Stag-Coloured-Wiring-Diagram.pdf

[Dazza the Stag]

Thanks for the wiring diagram Bullstarz
Den - great suggestion and detail, so i unplugged the wires as suggested and the fan did stop - so hopefully its just the switch. I will try and find a replacement. Out of interest where did you get yours from, just so I can try somewhere else given your experience with the quality.

[Goldstar]

I would look for a decent second hand one from one of the traders on here

[DZP]

Hi Dazza,

I sourced my heater switch from Rimmer Bros (131812).

Den