My Whirlpool Duet Washer, model number WFW9400SW01 will not turn on. The button lock is off and does light up indicating power to the front panel/unit. Any ideas?

If you are mechanical and are not afraid of small wires you can try this. I had the exact same problem on my machine. i very slowly diasssembled the machine. not hard to do. removed the top. unscrews from the back and slides to the back to come off. remove the door. unsnap the plastic plate that goes around the door.it is held on by small snap clip that pop off if you use a small flat screw driver to pry it out. remove detergent tray. and screws that attach it to the inner box. now the hard part. remove the face plate. it unsnaps similar to large door plate.very carefully unclip the circuit boards. they are held in by plastic clips around the outside and white plastic clips in the middle. you must gently pry up and release these clips one at a time. a second person is helpful, so are small needle nose pliers. clean both circuit boards very gently with isopropyl alcohol and qtips. mositen the qtips and clean every inch of the boards. be very careful not to bend or crack anything. you must get all the yellowish flux and any other corrosion growing on the board off. there is one more board that must be cleaned. the power supply board. it is mounted on the top right side near where the face plate wire come through. this is not hard to remove it is held in by small clips. the tricky part is the wires. they are all designed so they cannot be plugged in incorrectly but i have seen what people are capable of. make a map. number them with a sharpie so you know where they go. remove this board and clean it the same way. this on will probably be the worst offender. i cleaned all the boards reassembled and it works like new. below the door is a panel that should also be removed. there is a removable drain filter that should be cleaned out. i found pens and toys in mine. the machine could not pump out the water fast enough and would shut down and trigger f70 and f 20 codes.

I had the same problem. Inside the door there is a little black button that sends a signal to the panel telling it that the door is closed so that it will allow the washer to start. Mine broke off. I did my own fix it by using foil to fill the hole holding the button in permanently, then taped it. I will eventually get some superglue and glue the black piece back on. But my washer is working again. ( This was only discovered after I took it all apart, because i thought it was in the "start" button.