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Old 01-05-2013, 04:38 AM
pautler pautler is offline
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Attached to this post is the diagram for the keypad matrix from the tech sheet for my model.

I tested all of the 'button pushes' with my multimeter in diode mode, and they all seemed fine as follows:

P1-13 (+) -> P1-5 (-), push 'normal wash' => .78V
P1-13 (+) -> P1-4 (-), push 'Heavy' => .78V

P1-12 (+) -> P1-5 (-), push 'Rinse Only' => .78V
P1-12 (+) -> P1-4 (-), push 'Start' => .78V
P1-12 (+) -> P1-2 (-), push 'Cancel/Drain' => .76V

P1-11 (+) -> P1-6 (-), push 'Energy Saver Dry' => .80V
P1-11 (+) -> P1-4 (-), push 'High Temp Wash' => .79V

I also tested most of them with my leads connected with opposite polarity, and they did not show any reading (as would be expected, since the diodes should only pass current in 1 direction).

Now, my question is with regards to the 3 diodes that are shown all the way on the left side of the diagram - they are marked D6, D7, & D8. Based on the diagram, it would seem to me that my diode tester should always show a reading (without any button press) for:
P1-11 (+) -> P1-1 (-)
P1-12 (+) -> P1-1 (-)
P1-13 (+) -> P1-1 (-)

However, I don't. My meter shows 'overload' (open circuit) for all 3 of those connections. BUT, if I connect the leads in the opposite direction for P1-12 (-) -> P1-1 (+) then I do get a reading of .76V. The other two paths show 'overload' regardless of which way I connect the leads.

Is this indicative of a problem with the keypad/console, or is this expected behavior? Like I said, I really don't understand the purpose/function of those 3 diodes on the left side of the diagram - I suspect they might have something do with grounding?

I have a new keypad/console on the way from APP, but I'm just not sure that it is going to fix my problem. I'm still wondering if I might have 2 faulty control boards.

Thanks in advance for any help you might be able to provide!!

-Joe
Attached Images
File Type: jpg KeypadMatrix.jpg (81.7 KB, 12 views)
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