Hello there and welcome to Just Answer. My name is ***** ***** I will be assisting you today. I am an engineer with over 30 years of electrical and electronic training, repair and installation experience. I will try and answer your question accurately and precisely so that we can get you on your way.
The usual problem here is a loose wire or connection in the DIN plug that connects the three pedals to the piano.The connector has a small screw which, when removed, allows you to pull the connector apart. I would start there and see if any of the small wire connections are broken.Can you do that and let me know?I'll be here.