LOCKED THE LOCK APPEARS ON THE TOUCH PAD ON THE START BUTTON AND MICRO WILL NOT GO ON

" 1. CHILD LOCK
The Child Lock prevents unwanted oven operation
such as by small children. The oven can be set so
that the control panel is deactivated or locked. To
set, touch Custom Help, the number 1 and Start/
Touch On. Should a pad be touched, LOCK .
.. ON will appear in the display.
To cancel, touch Custom Help and Stop/Clear. "

Also, to find manuals........

The "lock" function is nice if you have kids who like to push buttons. It disables the microwave oven to prevent it from running unnecessarily,
To disable the lock feature push the "STOP-CLEAR" button. Then press and hold the "START" button until 'locked' is no longer shown on the display panel.
To re-lock it, do the same thing until 'locked' appears on the display.
Have a nice day.

As with most situations, it depends on the model number, but try this:

To set child lock:

1. Touch STOP/CLEAR pad.

2. Touch and hold 0 pad more than 4 seconds. LOCKED will appear in the display window and oven will beep twice.

To cancel child lock:

1. Touch and hold 0 pad for more than 4 seconds. LOCKED will disappear from the display and the oven will beep twice.

The Child Lock prevents unwanted oven operation such as by small children. The oven can be set so that the control panel is deactivated or locked. To set, touch CLOCK, the number 1 pad and then touch the START pad and hold for 3 seconds. Should a pad be touched, will appear in the display. To cancel, touch CLOCK, the number 1 and STOP/CLEAR pads

Hi there,

It sounds like you've activated the child-lock - this would disable all of the digital buttons.

To switch the child-lock OFF, simply press and hold the START button for about 4-5 seconds until "LOCKED" disappears from the display.

To switch the child-lock ON, press "STOP/CLEAR" button once, then press and hold the START button for about 4-5 seconds until "LOCKED" illiminates on the display.

If the buttons aren't working and "LOCKED" is not displayed, then you may have a defective touch control pad.

Hope this helps - please let me know if you need further assistance.

Regards,
BElectric

The first thing I would suggest is a hard reset. Unplug the unit for a minute or so. Then plug it back in, set the clock and try again.

If that doesn't work, leave it unplugged for about 5 minutes. Then let us know if the hard reset does not fix it.

The owner's manual is online here and it covers the child lock:

To set the child lock.
Touch and hold
ENTER/START
pad more than 3
seconds. CHILD
LOCK ON will
appear in the display
window with two
beeps.

To cancel the child
lock.
Touch and hold
ENTER/START
pad more than 3
seconds. LOCKED
will disappear and
you hear two beeps.

We're happy to help you with free advice and we'd appreciate your thoughtful rating of our answer.

Here you go.

The Child Lock shuts down the control panel pads to prevent
unintended use of the microwave oven.
When the control is locked, only the Vent Fan and Light pads will
function.
To Lock/Unlock Control: The microwave oven and Timer must
be off. Touch and hold START for 5 seconds until 2 tones sound
and a lock icon appears on the display. Repeat to unlock and
remove the lock icon from display.

Try this:

To cancel the child lock.
1. Touch and hold ENTER/START pad more than 4 seconds.
LOCKED will disappear and you hear two beeps.

Locking or Unlocking the oven control panel
1. Access Select Function Menu
2. Turn knob clockwise until Lock Keys is flashing
3.Touch Start. Key Pad locked is displayed.

4. To unlock keypads, touch cooking mode and hold for 5 seconds. Display will read unlocking key pad

5. When unlocked the clock will again appear in the display.

According to the owner's manual for model KHMS155L:

To Lock/Unlock Control: The microwave oven and Timer must
be off. Touch and hold START for 5 seconds until 2 tones sound and a lock icon appears on the display. Repeat to unlock and remove the lock icon from display.

You can download the manual here:
http://www.kitchenaid.com/custserv/service.jsp

We're happy to help and we appreciate your thoughtful rating of our answer.