You are correct, the model is a 665-15812990, I had the last three #'s wrong.
I did shut the power off for a day, no luck.
I did get the tech brochure out. It doesn't get into details about the keypad other than to show it as an input to the electronic control unit. I did successfully jumper around the ECU/keypad right at the ECU connectors and got the fill solenoid, pump motor, detergent door solenoids, etc. to work. Resistance is OK on the thermostat and heater. It seems like the downstream circuits work but it isn't getting the right commands upfront from the ECU.
The unit does not seem to go into diagnostics mode as described in the tech brochure. I hit the key combo described, and the 'lock-on' and 'water heat' lights flash in unison, 3 seconds on, 3 seconds off. While these are off, the 'no heat' light comes on. I cannot advance through the cycles as described in the tech brochure.
Based on the above, I suspect the keypad has to be bad. Of course, that’s what I though about the ECU too…….
Any suggestions besides using a grenade and insurance before buying the keypad? Can the keypad be tested? Or should I just suck it up and buy one?
Thanks again for replies!