I had the same trouble and managed to fix it myself. inside the switch are contacts for left and right separated by a piece of plastic with a tiny gap each side that is the centre off position. When it was new it had grease on it, this grease has gradually been pushed into the gap between the contact and the centre insulator, over time tiny particles of brass have been rubbed off the contact and have also ended up in this grease causing a short circuit while in the off position. Take the cover off the steering column, remove the switch, 2 screws and a connector is all, and gently open it up, clean up all the grease that is there and get those gaps cleaned out, put a smear of fresh grease on the contacts, just watch that the auto switch off cam slots back into its recess when reassembling. I have had no trouble since.
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Good Luck
Ron
Ron
July 2006
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