The problem is caused by fine metalic dust from wear on the switch contacts being trapped by grease in the indicator switch, the switch only feeds a small current to a relay, this is capable of being passed by the metalic grease and is why the indicators come on intermitantly.
The solution can be by complete change of the switch with new or removal and squirting WD40 or similar into the indicator section of the switch. The contacts are not easily seen or accessed this is why you will need to use a presurised spray with a fine tube attached.
The existing switch CAN be dismantled but requires care and there are a number of loose parts that can be misplaced.
I have done this repair to my daughters car with success.
steve barnsley
January 2009
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