Heater hot fan - running veeeerrrrrrry slow

[suffolkfox]

Thought my hot fan was not working, but having removed cover and accessed the feed wires, I found the voltage range being applied to it was in the range 1-2V, hence it does run but only at about 10 revolutions a minute! Bypassed the supply with a direct feed from the battery and it ran up easily to full speed. So, fan OK, supply is getting through to it but is too low. Any ideas? The ribbon cable from the switches must be intact for the supply to be getting there at all (it speeds up from slug to ambling snails pace as the knob is turned and the flap valve activates).

Options?
Bad earth (where the hell will the earth be)?
Duff switch (how do I test it)?
??

Guts of car hanging in passenger footwell at this moment

[speed8]

Daft question but I assume you have turned the knob.

[dean_ratpac]

suffolkfox said:

Duff switch (how do I test it)? ?? Guts of car hanging in passenger footwell at this moment

could the fan setting be stuck on the lowest setting or blown at lowest level? have you any photo's of what you're doing?

[cerber450]

suffolkfox said:

Thought my hot fan was not working, but having removed cover and accessed the feed wires, I found the voltage range being applied to it was in the range 1-2V, hence it does run but only at about 10 revolutions a minute! Bypassed the supply with a direct feed from the battery and it ran up easily to full speed. So, fan OK, supply is getting through to it but is too low. Any ideas? The ribbon cable from the switches must be intact for the supply to be getting there at all (it speeds up from slug to ambling snails pace as the knob is turned and the flap valve activates). Options? Bad earth (where the hell will the earth be)? Duff switch (how do I test it)? ?? Guts of car hanging in passenger footwell at this moment

Ello mate,

Take the switch out and check that it varies the output form it. If you have a meter for volts and ohms then set it to ohms the results arent that important just the fact that they will vary. If not it does sound like it could be faulty and stuck or set to the lowest setting which would do what your describing.

Craig.

[SI-PEN]

Don't know, but wouldn't this work on a Potentiometer!!

If so then I'd say its bu@@ered.