795.74053410 Kenmore Elite Refrigerator (LG) Working too good?

[rickgburton]

I couldn't find any reference to updating the board in the LG info I have and I don't see any USB connections on the board. If it has an update on it for the new compressor then replacing it with a new board, it won't have the update. I'll check and see if I can find a tech sheet and wire diagram and look for information regarding the update. I'll ask the other techs if they know anything about this.

 

[jasew503]

I couldn't find any reference to updating the board in the LG info I have and I don't see any USB connections on the board. If it has an update on it for the new compressor then replacing it with a new board, it won't have the update. I'll check and see if I can find a tech sheet and wire diagram and look for information regarding the update. I'll ask the other techs if they know anything about this.

Thank you! The jig he used looked like the one in the link below. Before the labor was performed, 3 boxes were delivered to the house, 1 was the compresor, another was the dryer unit with some parts, and the 3rd was this jig with some yellow documents identicle to the ones in the link below. The jig had a USB port on the end, and a harness which he used to connect directly to the board. The USB port end of this jig was not used at any time. He performed this software update with the fridge unplugged from power, which I thought was interesting as I'm pretty tech saavy and figured there had to have been power to the board in order to flash anything to it, unless this jig wrote directly to an eeprom of some kind. Anyways, here is the link I mention: https://pcrichard.zendesk.com/hc/en-us/articles/360031308531-LG-Universal-Compressor-CNZ201900136-01

I'll pull the compressor cover off tonight and look at the model number of the compressor, and get the model number of the control board in my unit as well just in case that may help.

Thanks again!

 

[jasew503]

I couldn't find any reference to updating the board in the LG info I have and I don't see any USB connections on the board. If it has an update on it for the new compressor then replacing it with a new board, it won't have the update. I'll check and see if I can find a tech sheet and wire diagram and look for information regarding the update. I'll ask the other techs if they know anything about this.

Hello again!

The New "Universal Compressor" model is: FLS075LANA, it has a red sticker on it that reads: "Software Update Required, see letter inside box"
The model number sticker has the following information on it: "Linear Compressor / R134a / Inverter 0-225V 56.5Hz"
The Control/Main board that was flashed with new software in the unit is model: EBR789406
The tech put a large yellow sticker over the Control Board access cover that reads:

-"This PCB has been S/W Updated to compatible with FLS075 Type of compressor. If you attempt to replace PCB, please update S/W"
-"Failure to update Software will result in improper cooling."
-"If you do not have S/W writing Jig or have difficulties with Software update, please contact: LG Technical Call Center / Call to STAC (Sears)"

Attached are pictures, the picture of the Control Board shows an unplugged harness, I unplugged it while checking resistance values and making sure they were all able to send a signal through the wiring it the back of the fridge.

If needed, the OLD compressor that was removed and had failed model was: FLB075LANA

Thanks!

 

[rickgburton]

Stand by

 

[rickgburton]

Our tech sheet guru bigbuck was able to find a copy of the that service bulletin. A couple techs had heard of something similar. This is something new for LG. The date on the service bulletin is only 7 months ago so if you're not an LG authorized servicer you won't have any of the information yet. This what our service tech jeff1 said:

Glad we refuse LG calls Never hear of this update before, but when I log into our parts depot it does now say we must contact LG before they will allow us to order an LG compressor now.

I read through the bulletin. That, along with what you're telling me and this picture:

This is a professional compressor installation. You can tell a lot about a tech by his work. It's my opinion the compressor replacement and software update was done correctly. That brings us back to the freezing issue. Since the thermistors checked good that also brings us back to the control board. The control uses the input from the thermistors along with compressor run time and length of time the defrost heater was on during the last defrost cycle to determine when the compressor and fans should be on. Somewhere in that service bulletin (I'll post a copy) it says the new control boards have the update on them.

LG CSP30020907 Svc Pcb Assembly,onboarding - AppliancePartsPros.com

Svc pcb assembly,onboarding CSP30020907 / AP6892813 made by LG

click.linksynergy.com

 

[jasew503]

Thanks for all the excellent information!

For reference: I spoke to a guy today that is a independent tech that works on LG's all the time, he stated the boards in these frequently need to be replaced even after a software upgrade with this new compressor installed. He also stated that I should check the heater voltage reading when put in Test Mode 3 (three button presses of the diag button on the control board forces defrost mode and heater to run) and it should read ~110-125v. That is something I have not checked, yet...

 

[rickgburton]

I can tell you you don't have a heater problem. If the defrost cycle wasn't working you wouldn't have all that freezing going on.

 

[jasew503]

I can tell you you don't have a heater problem. If the defrost cycle wasn't working you wouldn't have all that freezing going on.

Hey there!

So I ordered a new control board, new board is CSP30020907 and has the "REFRESH GEN 3" for the new compressor. I installed the board which took about 3 mins, and plugged the fridge in and let it run all day and night. Fridge temps and freezer temps were too warm (freezer above 32'F and refer above 40'F at any setting). The next morning there was an error on the display of "r DH". I unplugged the power and let it sit for about 10 minutes, then plugged it back in and the error has not come back, the temps seemed to be a little better but freezer still never gets below 25'F. Unplugged it again and left it overnight with the doors open to warm up and dry out. Plugged it back in, same result.

The fridge now works a little better, however the freezer never gets below 25-29'F when set to any temp, and the fridge tends to stay around 32-35 when set to 38'F on the control panel.

Should I replace all thermistors and defrost fuse/thermistors as well at this point? All the thermistors had good readings when tested, but that's the only other thing I can think of.

Thanks again!

 

[rickgburton]

Hmm... if the thermistors test good, they're good. Sounds like the problem is somewhere else. Did you go from freezing to not freezing? Might be a refrigerant leak.