I inherited my Kenmore Elite Range with my house. Albeit, a nice range, it is turning out to be quite the pickle to diagnose the issue with. When we bought the house, the unit showed an indicator light for the front right burner (3 element burner), and that burner did not work, though I could control it with the keypad (i.e. I could turn it on, but it would not work).
About a month into having it, I noticed the oven lock mechanism wasn't working properly, and I would get an intermittent error code. I circumvented that issue by setting the lock to unlock position and the error code didn't seem to return (seem to recall it being an F9 error code, but not certain).
Four weeks ago the real fun began. My wife called me telling me she was trying to clean under the display and though she didn't describe it this way, she basically shorted the line in terminals to the stove chassis (or whatever you might call it). Sparks flew and the conductor on the L1 melted a bit (though not completely), and the cooktop displays (all five of them) began to display an "F7 02" read out with a constant beeping. She flipped the breaker until I got home. I checked to see if there were any obvious shorts, connected a loose ribbon and didn't notice what she had done at the time. I flipped the breaker back on, and the range worked fine, no error codes.
Flash forward, one week ago, the F7 02 error code returned and rendered the cooktop units useless, and I could not clear the error code. I researched it a bit, and due to the Thanksgiving Holiday, did not have the time to try the full diagnosis... so I just ordered the control board (i.e. clock unit as SearsPartsDirect.com calls it), as that seemed to be the most common association with this error code.
Two days ago (yes SPD missed the Wednesday delivery date needed for Thanksgiving), I got the new control board. I swapped it in, hit the breaker and everything worked great... for about 20 seconds. I turned on the cooktop units, checked the oven, and all seemed fine. As soon as my elation peaked (about 15-20 seconds in), the cooktop controls stopped working, then the inevitable happened... yes, the return of F7 02. I never could achieve this with the old board, and couldn't get the new board to duplicate this series of fun activities.
So today my dad and I tore the bugger apart. I diagnosed the front right burner issue (element is fine, but thermocouple is bad). We also diagnosed that the motor on the door lock may be bad (though it was hard to be certain as it could have been the switch). Without a logics schematic, we couldn't really do much testing on the boards themselves, but there was one questionable part on the adjacent control board (some of the plastic covering on the board had come off though the traces seemed fine).
After 4 hours of testing resistance across about every resistor and circuit we could physically manage, we threw in the towel. It's hard to imagine anything other than one of the three boards or something directly connected to them aren't the source of the issue, especially since the new control board seemed to fix the issue momentarily. The challenge is understanding why the new board worked momentarily and then seemed to fall in line with the business as usual F7 02 code.
Any insight you can provide on this matter would be mucho appreciando!!!