My blower stooped working so I removed it and applied power directly to the terminals & it is OK. I assumed that the electronic module is faulty, but it could be the switch contacts on the rotary fan speed switch. I intended to replace the module £120 from dealer, but it could be the switch is faulty not the module. The heater/aircon blower is different in aircon equipped cars. There is an electronic module bolted to the casting that is not present on the non aircon blower. This is connected to a 4 pin plug. Two wires are heavy, probably 2.5 sq1 mm, and the other two are very thin. The rotary switch has 5 posn, so presumably it has resistor or some elements on it to produce a variable voltage to the electronics module. I have tried measuring the resistance between the two thin wires two each other & to ground in each position & found no difference in any position. This suggests that the contacts are open circuit. Can anyone expand on this & suggest further tests? It should be possible to test the module in situ by connected the control pins to a pot connected betyween +12V & ground.