TC reported hissing sound come fromwiper when it is in off position. ~~~~~ TC reported hissing sound come from  wip    #3549 A/S wiper control knob no hissing sound.When on off position.Cycle a few times confirm no hissing sound.A side washer and    wiper able to function.Replace new wiper blade and clean windshield function test wiper ok. Done by Saini/Haslan/Asruddin. 15/08/21