You need a test meter and the ability to use it. Open the panel and check if there is power to the on/off power switch and check that the switch is working. Also look for a fuse on the control board. Some have them and some models don't. If there is power getting to the control board and it doesn't work, then you probably need a new board. If you are not sure what you are doing, call a service company. Remember electricity can be fatal.
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