740/760 wiper switch repair

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These switches are prone to a comon fault - the wipers do not return to parked position when the switch is moved to the off position. Wash/wipe may also be affected.

To rectify, remove from car, drill out the two rivets at the rear and remove, and slide the two parts of the assembly apart, taking care to keep the arm within the larger of the two parts of the casing. There are two sliding contacts built into the arm, with a spring between each - there is a further spring between the arm and a locating block which has a small roller on the end - this gives the switch its location - take care not to lose the roller! Clean the contacts.

Having carefully dismantled the switch, examine the flat copper tracks on the smaller part of the casing and you will probably see a place where the sliding contact has caused a depression on two adjoining strips. Flux this well and fill each depression with solder, and then scrape off surplus until dead flat. Solder quickly - for a few seconds only - as you want the copper to disperse the bulk of the heat before the plastic melts.

There are a further two sprung contacts on a bar on this smaller part of the casing - clean the contacts with some fine emery paper or at a pinch wet and dry.

Apply a very thin film of vaseline to the contact areas (I used grease, being out of vaseline!) and then reassemble, replacing the rivets with suitable long screws. This should keep the unit operating for a few more thousand miles yet.

Time taken about 1 hour.

Regards

John Davies