The wiper motor much like the power window motors have an internal thermal cutout to protect the motor from burning out if stalled or overloaded.

Probably not the fuse as it would blow under overcurrent and the wipers wouldn't restart.
Still check or replace the circuit fuse.

More indicative of the thermal cutout automatic reset.

Lubricate your wiper mechanism.
The mechanism tends to run dry which increases friction and load on the motor.

You need to lift the cover to check and lubricate the pushrod with a waterproof grease...silicon or white lithium/ptfe works well.

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1971 280SL ROADSTER
1988 300CE TWIN TURBO WIDEBODY
1994 E320 CABRIOLET
1999 C43 AMG
2005 G55K AMG
2008 CLK63 AMG BLACK SERIES