KCMS145JSS0 - Overview

Remove top grille (2 screws), undo control panel (1 screw). Tilt down control panel, switches are on the left. There are actually three switches that are involved with the door, two horizontally mounted, one vertically mounted. This would be an EASY REPAIR, but it took me a while to figure out which of the three switches was bad, and also took a while to figure out that there is a plastic rod that inserts through the hole in the switch body. Once i figured this out went like a breeze. Lower horizontal switch was the bad one, but since the kit came with two switches i went ahead and replaced the upper horizontal one as well. IT appears that the horizontal switches are probably more likely to fail than the vertical switch based on the position of the switch and force angles. Works great now!

The repair went well...I am so glad that I read this info before buying a new microwave....it saved me lots of money. I did have a repair man come and look at it and he told me to buy a new one but it cost alot of money when it wasn't necessary. I did the repair and I was very proud of myself.
Three men watched a woman fix this and it was no problem...they were impressed also....

Unplug the unit before servicing. Need phillips screwdriver. Open door. Use step ladder to access and remove 2 small screws from top of the room air diffuser at top of unit. Slide diffuser slightly to the left to align the diffuser's plastic tab on the left side to rotate toward you. (The wires for the front control panel are at the far left side of this difuser, but difuser is slotted for easy removal). Once the difuser is removed you will see 1 screw at the top that secures the pannel cover on the left side of the unit. Remove screw and slide this panel slightly up and out. This exposes the plastic frame that holds the upper and lower door switches. To locate the door switches and observe how they work, close and open the door and watch the door (bayonets) open and close the micro switches. Do the (red) buttons on top of the switches move up and down when the door bayonets push and release? If the buttons do not "pop" up when opened the switch is defective. The switch frame is secured with 2 screws. Remove screws and rotate the unit out for easy access to the micro switch(s). The internal (spring?) on my unit that is suposed to allow the red (visible) button on top of the switch to "pop" up when the door is opened was broken. Carefully pry the switch outward while being careful to lift the plastic holder-piece that holds the switch in place. Be careful, there is a small pin on the frame, so rotate the switch OUT toward you while lifting (carefully) the plastic holder-piece (you will see it on top of the switch). You can use an ohm meter to test the continuity of the switches. But if the buttons don't "pop" they are defective. Replace switch and reassemble.