Hi all,

Newbie here! My Climatronic fan stopped working on the weekend. Lights on the dash all go on and the actual heating element works but the fan itself no longer blows.

Took the blower motor and controller/resistor part out (part 3C0 907 521F) from under the glove compartment and ran some tests. The fan works fine if connected straight up to a 3V battery source but if I put the same 3V through the resistor/ controller I get nothing.

Have checked the plug adapter in the car which plugs into the resistor (4 wire connector). With a multimeter on the brown wire and the middle bottom wire (black/white) I get varying voltage as I increase the fan speed. Therefore assume the fuse/ dashboard controller is OK. So points to something not right between input to resistor/ controller and output of controller.

Any way to test the controller unit itself? I would guess it includes a relay of some sort as it has 4 wires coming in to it.