The resister plate, wires break because of the heat in the wire, I went to scrapyard and looked at about 6 cars, all had broken resistors. Best option to repair with new resistors.
The resistor plate (3 resistors mounted on it giving the different speeds) is mounted in the heater ducting under the glove box.
1: Remove trim under glove box
2: Remove 2 bolts (I think) and lower glove box.
3: Look for electrical connection and unclip.
3: Undo 2 srews and remove resistor plate.
Takes about 15 mins to remove and same to put back and maybe 30 mins on bench with a solderig iron.
Parts can be found on ebay or electrical component supplies ,for around £10.
Don't have resistor values but kit on ebay supplies correct ones.
Alan A, March 2010
