Water remaining in the tub would normally indicate a problem with the pump. AquaSmart has a reversing pump with a flapper valve ... one direction for drain, other direction for recirculation.

However, Regular + Easy Iron = Fault Code 130, which is "single rotor position sensor error" -- The control board found an error in the data pattern received from the RPS (which is related to the main SmartDrive motor, not the pump).

On an LED AquaSmart, Diagnostic Mode is accessed by turning power off, press/hold High Efficiency, then press Power at the same time. Release the buttons when the console powers on.

Confirm the last recorded fault code by pressing Spin three times until BOTH Slow and Hold are lit. The cycle selection lights indicate the fault code. Add up the numbers of the lights that are on --
Regular = 128
Heavy = 64
Delicate = 32
Sheets = 16
Colors = 8
Bulky = 4
Easy Iron = 2
High Efficiency = 1

To test individual components via Diagnostics, press the Spin button until all the spin lights are on. Then press buttons as below to turn the stated function on/off:
Regular = hot water
Heavy = cold water
Delicate then Regular together = detergent dispenser
Sheets then Regular together = bleach dispenser
Bulky = pump drain
Easy Iron = pump recirculate

To test the pump, fill the tub about 1/4 full via hot or cold as above. Run the pump in recirculate mode, observe that water recirculates and DOES NOT flow out of the drain hose. Switch the pump to drain, observe that water drains and DOES NOT flow out the recirculation port.

Thanks for the info, dadoes!
I have printed them out. Now to go down to the washer and see what happens. I will post back as soon as I have the results.
Thanks again!
kcred

Okay.
In diagnostic mode, the fault code was two, as only the Easy Iron cycle selection light was lit.
I did not run through all the functions, but both the hot water and the cold water worked fine. Also working fine are the Pump Recirculate and Pump Drain functions.
So this rules out the pump as the problem.
So far, so good! Anything else I can try to figure out the cause?
Thank you for your time and effort in this.
kcred

So after the whole diagnostics process, I thought I'd give the washer another chance.
After filling the drum with about an inch of water, the hot water inlet hose started again making the loud Ka-Chunk noise, and you could visibly see the hose jerking/pulsing as the noise was made. So it's something related to that.
Guess I'll unplug the machine and wait for the service tech. I'll be sure to let you know what he finds.
kcred

Hmm. There is no Fault Code 2 listed in the service info.

There shouldn't (theoretically) be any difference between the hot water incoming flow during diagnostic vs. filling to run a cycle ... except that the flow may be moderated during fill for temp control. It shouldn't cause any hammering on the hose unless AquaSmart ATC does that a different way than smoothly moderating the flow as do other models. The hose hammering did not previously occur?

I'm not intimately familiar with the cycle sequences on AquaSmart to the degree that I am on agitator models. Wondering why it triggers fill upon starting when advanced to the Final Spin. Should start with draining. Maybe try turning the hot & cold faucets off, advance to spin and let it run to see if it stops with a Fault Code so you can check/confirm what is that code.

Is it only the hot hose that hammers? Start a cycle set on cold fill, let it go until a fault triggers.

Thanks for the follow-up, dadoes. I will try your suggestions when I get off work today.
kcred

So I never got around to further troubleshooting this problem as the repairman was scheduled today. I was at work but here is what happened according to my wife:
The tech stopped by. Had a look around and the washer seemed to work. (It turns out the problem is occurring in the rinse cycle and he didn't wait for the rinse cycle). The wash cycle appeared to work, the pump and motor both appeared to work, so he told my wife to use less soap and left!
One thing about this "tech". He said he had worked on "several" F&P's, but he had no fault codes for this model. My wife had to print off the ones I had saved from dadoes in an above post.
Anyway, my wife goes to do a load later today and sure enough, the same problem occurs. She immediately called the service company. The tech was still in the area and came back by. When confronted with the problem, he got on the phone to his tech advisor, who helped him troubleshoot.
He will be back next week to r&r the Control Board, on the receipt as SUB PCB, MTR 26 426 421226USP 1, at a cost of $267.96. With another $141 in labor, that is a total of $432.88.
Glad I got the extended warranty. I just hope it fixes the problem.

Just say ... SearsPartsDirect.com lists the board at $198.49. Swapping the board is not difficult ($141?!), so a competent DIYer could save the service charges.

The fault codes are the same as all Phase 7 agitator models, with the addition of a few codes specific to the AquaSmart models. There should be a tech sheet in the console that lists the most common codes (but probably not all of them). I only referenced one code (130) above in this thread. There are many more.

I'm curious as to exactly what malfunction and fault code is occurring ... and whether changing the board will fix the problem. Please advise what happens.

Thank you for the additional info. He did find the tech sheet in the console. I told my wife not to let him take it.
He's scheduled back on Tuesday 08/23. I am off work that day so I will be here when he comes back. I'll be sure to post the results.

Got a call from the repair company today. The part was not delivered on time, so they will be out this Thursday, 08/25, instead of tomorrow. I will update then. Thanks!

He just replaced the Control Board. Not looking like it helped.
Dadoes, if you happen to be online now, let me know. Maybe you can help this tech.

The Control Board didn't help.
Now he's thinking it's the sensor on the motor. The motor checked out fine.
He'll be back Tuesday the 30th. Will update then.

Code 130 referenced above is related to the motor RPS.

His parts order today included a Module, #26 426 420776P 1 at $48.65 and PCB MTR #26 426 421226USP 01 at $131.30.
Looked like replacing the Control Board was fairly easy.
Thanks again, dadoes. Will update on Tuesday.

420776P is the RPS (rotor position sensor in the SmartDrive motor). Just for reference, Sears lists it at $17.99.

421226USP is the motor control board. Interesting that it was quoted at $267.96 in your 8/16 post, but $131.30 today. Wonder what's up with that?

I was thinking maybe this is a running total of parts ordered, till I saw the price difference. I don't know. Also funny was that F&P UPS'ed the part directly to me and not the repair shop. The tech seems like a nice guy, I just hope he's on the right trail this time. Laundromats aren't the greatest place to pass the time, lol.

This part: 420776P is the RPS (rotor position sensor in the SmartDrive motor). Next Tuesday is what we're shooting for now. They say the part will be delivered via UPS on Monday, Sept. 5. I don't know if UPS delivers on Labor Day. Guess I'll find out.

Tuesday came and went. Washer still not working. I called the repair store. The RPS is still on back-order with F&P and no ETA. So I went to searspartsdirect.com and ordered a part from there. Part #420776P was $34, plus $30 for expedited shipping. (thanks dadoes for the part number). Part was ordered Tuesday with a delivery date of 9-9, the same day the repair tech is due here.
As of now, I haven't received a UPS confirmation that it will be delivered. The wife is going to call them today to confirm.
I sure hope this comes together Friday, as the next date open for the tech is Sept, 17.
Will keep you posted.

Sears ships from multiple warehouses as per stock location, but they don't always update their site regarding in-/out-of-stock status.

Interesting to note that your model WL37T26D comes up under two different product codes, with different RPS part numbers referenced. Apparently there was an engineering change during production. I assume your service tech noted the correct part, but you might double-check the product code on your machine's model label tag against the Sears listing for the part you ordered.

Thanks, dadoes. I have no idea where to look on my washer or Sears order for any product code.
Today Sears told my wife they were going to put my order on hold for a day or two to make sure this was the correct part. My new delivery date for the part is 09/13 and the new date for the repair tech 09/16. The repair center again said today the part was on back-order from F&P with no ETA.
So I'll keep my fingers crossed that the correct part shows up.
In the meantime, I'll be getting my mail forwarded to the laundromat, lol.

Product code is on a separate sticker (possibly has a barcode) somewhere on back of the machine, possibly down in-line with the model tag behind the console. My IWL12 washer is product code 96154 ... IWL12-96154 for Sears listing (which returns three choices).

Your WL37T26D returns two model choices. The SmartDrive rotor, stator, and RPS are different.
WL37T26DW1-96125A (RPS # 420776P $36.04)
WL37T26DW2-96113A (RPS # 438515P $17.99)

I just came up from the basement. My product code is W1-96125A. Which means I need part #420776P. Which is the part I ordered. Hoo-Ray!
Thanks you very much for all the info in this thread, dadoes. Your time and effort is very much appreciated. By the time this whole ordeal is over, I'm going to owe you a steak dinner.
Now if the part and the service tech ever convene here at the same time, I will be in business!

The part has arrived. The service tech will be here Friday to install it.
Maybe some light at the end of the tunnel after all.

Okay,
This is all second-hand info from my wife as I was not here when the tech came today.
He installed the new RPS module #420776P. The rinse cycle went fine. But, (and you knew this was coming), a new problem reared its ugly head.
Now the spin cycle has a problem. It will not advance up to the full spin speed. It starts to spin slowly but will not advance to the top speed.
A new fault code appeared, 40. According to the tech, this is related to the washer basket. He pulled the basket to see if any clothes might have gotten stuck in there. Nope. He did clean it out well while he was there. He then reseated the connections to the control module. No help there either.
He has now ordered a new control module, part #421226USP. This is the same part that was changed out the very first time. But I do not know if that tech kept the new module in the washer, or put the old one back in when the new one did not fix the problem.
So this coming Wednesday we will try again.
I have to give this new tech credit. He called his tech support and they did not know what it could be. He even called F&P and they did not have an answer either.
The good news is that fault code #130 is gone, the one associated with the RPS sensor. So that is working now.
Keeping our fingers crossed and getting sick of laundromats,
kcred

Fault 40: Basket check indicates the basket is not engaged to the drive cog even though the water level pressure sensor indicates the tub is empty of water. The basket floats slightly to disengage from the drive cog when the tub fills (for agitation), then settles back down when the water has drained (for spin). Basket check after drain has the motor pulse cw/ccw several times to confirm by inertia that the basket is engaged for spin.

1) Mechanical: Check that there are no clothes or objects under the tub or caught in the drive cog ... or excess suds causing the basket stay floating. Remove the basket, disassemble the clutch hub for inspection. Confirm the pressure sensor tube has not come off the control board (or the tub, although there should be a leak in that case) and is not kinked/pinched.

2) Electronic: Replace the control board.

I will print out your response (if that's okay with you) and give it to the tech when he comes back.
He did a pretty thorough job of checking under the basket and cleaning it. I don't know if he disassembled the clutch hub. As we live in a hard water area and use less than the recommended amount of soap, I don't think oversudsing is our problem.
A new control board sounds promising.

The new control module came in today, and the service tech is coming out tomorrow!
The reason I'm so excited over this is that the service provider of our extended warranty called earlier in the day. They said they couldn't ship the part until this Friday, and so we made a new appointment for next Wednesday. Then the part showed up. My wife called the provider back pronto and told them they better get out here tomorrow. They will.
Let us all hope this is the end of this ordeal.

The tech left, unhappy that during the spin cycle the basket didn't seem to be getting up to full speed.
He had replaced the Control Module with the new one, still did not come up to speed when advanced to the spin cycle. The basket went CW/CCW fine, just slowly. When stopped, the basket lifted up fine, no binding at all. The motor sounds normal.
He couldn't think of anything else, so I told him I would try a complete cycle and he left.
I got the flashing wrench during the spin cycle. Both the Delicate and Whites lamps are lit on the control panel.
Time to call him back I guess.
The only good thing is that the washer made it past the rinse cycle, showing the replaced RPS sensor is good.
Any help with this new fault would be appreciated.

It looks like Delicate and Whites equal a fault code 40. Delicate is 32 and Whites is 8.
Any idea what fault code 40 means?

I got a call back from the service company. They didn't know what a fault code 40 is, but the tech thinks the problem is in the wiring harness.
So a new wiring harness has been ordered and I guess it will be installed sometime next week.
Almost 6 weeks without a washer....

I re-read the thread. Fault code 40 is:
"Fault 40: Basket check indicates the basket is not engaged to the drive cog even though the water level pressure sensor indicates the tub is empty of water. The basket floats slightly to disengage from the drive cog when the tub fills (for agitation), then settles back down when the water has drained (for spin). Basket check after drain has the motor pulse cw/ccw several times to confirm by inertia that the basket is engaged for spin.
1) Mechanical: Check that there are no clothes or objects under the tub or caught in the drive cog ... or excess suds causing the basket stay floating. Remove the basket, disassemble the clutch hub for inspection. Confirm the pressure sensor tube has not come off the control board (or the tub, although there should be a leak in that case) and is not kinked/pinched.

2) Electronic: Replace the control board."
So I don't know. Maybe the wiring harness will help. Maybe not. I'm pretty disgusted and depressed right now.

Sorry to hear this, unfortunate situation for sure.

Wiring could be involved but there's no suggestion of that on the list of resolutions for Fault 40.

You've already replaced the RPS and controller ... but I'm wondering if somehow it's the wrong RPS ... which could contribute to the spin speed problem being as the RPS is directly responsible for feeding the rotor speed to the controller.

Basket RPM during spin can be checked via diagnostics.

A tangent thought ... any possibility that fluid has leaked from the integral balance rings at top/bottom of the basket? There will be malfunction if the basket weight is not within spec.

I'm not understanding why your servicer wouldn't have info on all the fault codes. The same fault codes apply as for phase 7 agitator machines, plus a few codes specific to AquaSmart, mostly related to the different pump.

Ahhh, I also just noted info that there have been changes on the suspension rods, and the latest rods require a specific controller version for proper OOB "bump detect" function. If the controller on an older version machine is replaced to a newer version controller, the suspension rods must also be changed. Supposedly a replacement controller *includes* the correct rods, but that may depend on what part number/kit is used to order the controller. This could possibly affect spin speed and basket sensing.

Contact me off-board if you would like copies of the info I have. I may not have the latest docs, which your servicer should be able to obtain.

Thank you, dadoes, for the info on the suspension rods. That sounds a lot more likely than the wiring harness. I will be sure to show it to the tech.
We will try again this Tuesday. With the new wiring harness. Who knows?

So a new technician came by today, the 3rd different one in 4 visits. He was ready to install the new wiring harness when he noticed that a previous technician had crossed the wires to the motor, attaching them to the wrong terminals! He could've just corrected the situation easily by connecting them correctly, but he said what the hey. Here's a new wiring harness, I'm gonna install it.
He did and it works! No more laundromat (hopefully for a long long time). So the whole fault code 40 was due to "technician error". We could've had our washer back a week and a half ago, when the new RPS sensor was installed.
Dadoes, thank you again for all the above help. It was very much appreciated. I have saved this info just in case.
kcred

Whew! Yeah, glitches can happen although service techs surely don't intend for it.