Car Heater

[stardelta]

The heater,or more rightly,the fan on the heater,only works on full speed. The three slower settings don't work. So, it's either full blast or nothing.
Could anyone explain the principle of how the fan speed is controlled please ?
Model is 2008 Fiesta

[jd_1984]

http://www.2carpros.com/articles/how-a-car-heater-works

May help??

[jake-the-peg]

Classic case

There is a 3 stage resistor this has blown so that only works on full.

http://www.fordownersclub.com/forums/topic/1130-fiesta-blower/ for a discussion I'm sure you'll find many others

Replacements about 15 quid

[johnk]

The low speed windings often blow if the pollen filter is not replaced