DW LG won’t drain properly

[ARQ]

Hi

I have an issue with dishwasher LG model # LDF8072ST, ser # 305KWSB0B462

it has an error code OE - issue with drain. It’s draining but, it doesn’t do it properly. Drain pump starts running, works 2-3 sec, stops, then again starts, stops and it does it 7 times, after that it stops, but a rest of  water is still on the bottom of dishwasher.

i replaced a drain hose, drain pump & main control board, but it didn’t help... Appliance with new parts are working absolutely the same like before...

I noticed that a drain pump (new & old one) is running constantly, without any interruptions, when it’s not connected to the drain system. I took a wires connector (for 3 wires), connected it with pump and started a drain cycle, it is running constantly. If I install a pump to dishwasher, start cycle, fill water, starts washing, I press to cancel for draining, it’s not draining properly again...

Did someone see this issue before? Any suggestions?

Thanks everybody.

[16345Ed]

Didn’t just install a new garbage disposal did you?

[Chat_in_FL]

Obstruction between the sump and the drain pump inlet? Since you've already down everything downstream of the drain pump outlet...

[16345Ed]

2 hours ago, ARQ said:

Thank you for your suggestions, but there’s nothing clogged there...

It sure seems like something is blocking water if pump runs unattached but doesn’t when it is. 

Bad check valve or small piece of clear plastic like plastic wrap. 

[Ian B]

Check to see if the drain hose is kinked when you installed the dishwasher back into cabinet. Definitely seems like a clog somewhere. 

[dave2543]

Hi Arq, on the fluid aspect, do you have an air gap on that drain line? If so,  Is it clear?

I could not find a wiring diagram of your machine online, did you have one you can post?  In some LG diagrams I found the float switch is part of the drain pump circuit.  

When you tested the new pump as described here " I took a wires connector (for 3 wires), connected it with pump and started a drain cycle, it is running constantly"  was the pump outlet hose connected, and the sump full of water, and was the end of the hose the same height above the pump as the highest point in your air gap or drain loop ?

For the pump to put a full electrical load on the circuit (current)  it must pump the water UP.  Intermittent starting/stopping under load could be a fault in the neutral side of the pump wiring, not the so called hot or line.  But without the wiring diagram, no way to tell what is in that neutral  circuit.

 

[ARQ]

Thanks everybody

[16345Ed]

On 3/4/2019 at 1:16 PM, ARQ said:

Thanks everybody

What was result?

[ARQ]

Nothing, I gave up...

[Mayo Appliance]

It is usually the case break assembly/sensor on the side of the dishwasher. You’ll also find that the rubber check valve at the sump to pump port has fallen off. I usually replace that if so. I carry that tiny $5 check valve on my truck.