In Reply to: answer posted by Paul T on December 20, 1999 at 15:08:47:
: The wiper arm is held on the shaft by one nut, possibly 13mm. The shaft is either tapered, or splined, but in any event, when the nut becomes slightly loose, the arm flaps about. Park the car. open the hood. bring your 13mm box wrench and gently tighten nut at base of arm, with arm where you would want it to be.-Paul T
I would add one further step to this fix. Apply some Loctite to the thread on the splined shaft. This will prevent the nut working loose again.
I experienced a similar wiper failure during a storm, and the two wipers clashed and locked together. Very inconvenient at 100kph.