Troubleshooting a GE Adora dishwasher - sprayer pump sounds dead?

Dishwasher Repair
1

Greetings,

I can use a hand troubleshooting the subject dishwasher. The problem is when I start a normal cycle, it fills with water as it normally does, and then when I should be hearing the motor running and water spraying/sloshing around as it cleans dishes normally, all I hear is an electrical hum coming from the bottom of the machine. When the cycle completes (or if I interrupt the cycle by hitting the RESET button), I’ll hear the drain motor kick in as it should, it drains the tub properly and the cycle completes. When I open the dishwasher up, the water is drained out but dishes are still dirty (duh!) and the soap tab is sitting half-dissolved on the bottom of the tub.

As for the control panel, all the indicator lights are working normally per the owner’s manual, and this behavior occurs no matter which cycle option I choose (e.g., normal, pot scrubber, rinse only, etc.). DW was purchased in 2009, so it’s about 12 years old now.

Any thoughts on how to tackle this? I’m handy with a multimeter & tools, but I haven’t messed with this dishwasher yet.

Thanks in advance!

2

Quick update - I found the schematic diagram and instructions for enabling the dishwasher’s diagnostic mode inside the dishwasher, and ran the available diagnostic tests.

The result is that the main pump motor won’t operate - it just hums. Measuring voltage across the motor’s terminals (Blue wire and White/Red wires) I’m getting a normal 120VAC, so I suspect the control circuits are fine - pump gets power when it’s supposed to. All other testable functions (drain pump, water valve, heater element, aux pump, and detergent/rinse aid) all check out fine.

Is it possible that something (food debris maybe?) is jamming up the pump and preventing it from running? If so, is it possible to take this thing apart and un-jam it? If anyone can point me to a good repair manual/procedure for this it would be appreciated. Shopping around for a new main pump unit I’m finding the part is expensive and not readily available.

Thanks!