Dear srs, I have seen in magazines and brochures that the widshield wiper in the w124 follows a cam and sweeps almost all the windshield, in my 1990 300e the wiper follows a circular path, leaving large areas at the upper corners of the windshield without cleaning.

What do you think is the failure and how do I fix it?

thanks for your advice.

The W124 wiper doesn't really get ALL the windshield. It gets more than if it didn't have the little cam mechanism, but it still leaves the corners behind. In fact, at first glance, it looks like it's just sweeping an arc. Have you watched the bottom of the wiper arm where it extends and contracts as it sweeps? You should be able to notice it do its little dance twice in each direction per swipe.

Mine doesn't extend or contract at all, maybe the cam mechanism is damaged

The extension motion happens very quickly so you may miss it when it is running. If you turn on the wiper on low speed with the ignition off and bump the ignition so the wiper sweeps a little bit at a time you should see it extend. It moves out roughly 3 inches give or take, from my memory.

Rgds,
Chris W.
'95 E300D, 408K

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