crazy idea, put on the aircon if it stops the air con pump needs renewing, had a corsa done this, it can be a problem especially at this time of year when people dont use aircon.... it should be switched on for at least ten minutes per month to save the system..
just an idea!!
...erm , how will changing the window winder fix it? (hilux.... air con>?!!!?) :lol:
isolating the source is the only way to find out what to change first... i would take a VERY large flat bladed screwdrive, and whilst making sure your hair/hands/genitals/facial features are clear of moving componants, use it to listen to certain areas..
press the blade hard against solid (non moving) bits, use the handle to listen to.. sound travels along the screwdriver ya see..
more than likely a bearing, mine play tunes if the weather conditions are right! :lol: