You will probably find that it's not the switch but in fact the regulator windings at the blower end. Look behind the glove box(passenger side) and find the blower housing/motor. Remove the panel where the wires go into it and you will see the little some metal windings.They are just loops of resistance wire. Each of these provide the motor with different amounts of power depending on the winding length. You will see that these are probably broken. It's iether £50 to replace or a bodge up repair where you can wire a 21watt bulb or two in series to lower the voltage to the motor. Leave the bulbs in the air flow inside the unit to keep cool. (the bulbs will obviously glow when the fan is on but it shouldn't matter.You will need to solder the bulbs using wire etc in place of the wire coils. Experiment, I did and it's been OK for a year or so with no problems. Please note I'm not an auto electrician so don't do this unless you know what you are doing.
Garry
January 2005
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