LG Dishwasherwill not cycle

[JGPE]

LG Dishwasher model LDF9810ST, SN 707KWZH02365 Starts normally through sequence #3 below (from another's earlier post), but then wash motor never starts. Instead, a rhythmic squeak/scrape sound begins, originating from either the inlet valve or behind it. Both wash water pump motor and sump motor have been replaced. Just tilted it again to make sure wash water motor impeller wasn't obstructed, vacuumed all lines, reconnected water & tried normal cycle. Same results. now about an hour into the 2:15 cycle waiting to see if it throws an error code. Seems like a relay switch or actuator is trying to function but isn't able to, just keeps making the noise.

 

LG dishwashers have a start-sequence that goes like this...

1) Close door (after selecting a cycle)

2) Drain Motor runs for approx 30 seconds

3) Water fills/enters tub

4) Wash Motor begins wash cycle

I'm assuming that you've had success with steps 1 through 3 but the dishwasher will not begin the Wash Cycle.

[johntech]

You need to check voltage to the motor when it should be running. If you have correct voltage then you have a bad motor. If not you need to check the  output to the motor at the control board.

[john63]

On May 16, 2016 at 4:59 PM, JGPE said:

LG Dishwasher model LDF9810ST, SN 707KWZH02365 Starts normally through sequence #3 below (from another's earlier post), but then wash motor never starts. Instead, a rhythmic squeak/scrape sound begins, originating from either the inlet valve or behind it. Both wash water pump motor and sump motor have been replaced.

Was the SUMP ASSY (Part number: AJH31248604

) replaced?

Or just the WASH MOTOR (Part number: 4681ED1004B

) and the drain motor?

How long ago was this replacement done?

[JGPE]

Sump Assy was not replaced. Just the wash motor and drain motor. Prior repair(s) include main control panel, then about a week later, a couple of wires at the base of the door which had their insulation abraded off before shorting and throwing the breaker. I'm sure this is what fried the control panel in the first place (thanks for the $350 in-warranty repair LG). Wires have been soldered & re-insulated with heat shrink tubing. Now the DW cycles through an entire wash as though nothing is wrong, but nothing happens after the initial fill except the water has gotten hotter. The soap dispenser doesn't even open. But the normal wash cycle (about 2:15 long) finishes without throwing any error code(s). I can open the door at any time and press the "normal" & "steam delicate" buttons simultaneously to cancel the cycle and this starts the drain motor emptying the sump.

I see no moving parts in the sump assembly. I've blown it out using compressed air followed by vacuuming with shopvac. Am I missing something? BTW, can I upload a short video with sound on this forum?

[JGPE]

Drain motor was replaced about 3 weeks ago. Wash motor just replaced last weekend. Prior electrical repair was 2-3 years ago.

[john63]

The drawback to replacing the Wash Motor (only)---is that the Motor Seal (part of sump body) is not available as a stand-alone part.

The percentage of failed replacement Wash Motors is quite high due to seepage leak.

It's always best to replace the entire Sump Assy (Part number: AJH31248604

)

[JGPE]

I'll check the voltage to the motor. When you say wash motor, you are referring to the white motor attached to the outside perimeter of the sump assembly and not the motor directly below with the windings visible? The latter I thought was the drain motor which the original showed signs of leakage. The replacement also showed similar signs when I went to replace the wash (white) motor. I had attempted maybe 5 cycles before draining and replacing the wash motor. Now I'm wondering if the replacement motor has already failed from the leak. And btw, what is that last motor on the under side of the sump? Does it actuate the check valve in the sump assembly?

[john63]

The Wash Motor is located at the bottom of the sump.

The Drain Motor is mounted on the side of the the sump.

The small motor---is the Vario Motor---which directs water to the lower wash arm---then to the middle and upper wash arms in an alternating fashion.

Press the RINSE---SPRAY---and POWER buttons at the same time and release all 3 buttons (test mode)

Press the DELAY START button 3 times (then close door)

The Drain Motor will be energized.

Press the DELAY START button 8 more times (then close door)

The Wash Motor will run.

Which motor sounds faulty?

 

[JGPE]

It's the wash motor. Starts to make the scraping sound described earlier then throws "CE" code. Didn't take but a couple cycles to leak & kill the replacement. Maybe the stupidest design I've ever seen. Shaft seal fails, killing the motor along with it and a complete replacement sump assembly is required all because of a what, $0.50 seal? Nice work LG.