• Please note, some of the links on our site are affiliate links (Learn More)

FIXED LG dryer advice after service manual troubleshooting - replace controller?

gherndon

Premium Member
Joined
Dec 29, 2012
Messages
13
Location
charlotte, nc
Model Number
DLE5977W
Brand
LG
Age
6-10 years
hi, LG dryer, model DLE5977W.

2 months ago i replaced the thermistor after unit not drying clothes completely and continuing to run at end of cycle time. sensor dry always resulted in clothes not being dry. timed dry worked, but display showed check filter and continuous "cooling" at end of cycle.

so, reading the service manual i opted to replace the thermistor, as it was a cheap ($13) part and was likely to be the problem.

after replacing, the dryer worked great for 2 months. just like new.

now, same symptoms, and i replaced thermistor again. i also used the service manual to check components:

resistance of thermistor is 10ohms, checked both existing and new part. resistance at controller interface (pin 5 and 6) is 14 ohms, at 65-68 F, is within spec. table 1, service manual.

unit self test, fails intermittently with LE1, thermistor open. it's not. doublechecked connector at controller, per diagnostic table, and the manual says "replace controller".

my question is, should i replace the controller? it's a $100 part, and i'm okay with the cost, but is there anything else that it could be, i.e. a bad wiring harness that i could check first? do these fail at this age?

i can't order the part until monday, and won't have it until wed with the holiday, so i'm asking here 'til then.

thanks in advance, george
 

Jake

Appliance Tech - Admin
Staff member
Joined
Aug 24, 2004
Messages
105,310
Location
McMullen Valley, Arizona
I don't have any experience working on LG products, Wild does, he may be here in the morning.

You can also ask at the Q&A section here:


Jake
 

gherndon

Premium Member
Joined
Dec 29, 2012
Messages
13
Location
charlotte, nc
thanks jake. i've asked my question in the area suggested. i'll look forward to a reply there and possibly one from wild.

appreciate the help.
 

Jake

Appliance Tech - Admin
Staff member
Joined
Aug 24, 2004
Messages
105,310
Location
McMullen Valley, Arizona
Ok, sounds good, keep us posted.

Jake
 

gherndon

Premium Member
Joined
Dec 29, 2012
Messages
13
Location
charlotte, nc
i've PM'd wildimaginations, but have also ordered a controller board from the site. i'll replace and update this thread with the results, hopefully on wed of this week.
 

Jake

Appliance Tech - Admin
Staff member
Joined
Aug 24, 2004
Messages
105,310
Location
McMullen Valley, Arizona
Ok sounds good, yes keep us posted.

Jake
 

wildimaginations

Appliance Tech
Joined
Jun 13, 2011
Messages
632
Location
Danville, California
I don't believe that there is an error code LE1. I think you're reading it as tE1 which is a thermistor problem. If you have replaced the thermistor and it worked find for 2 months before crapping out, you may have a wire connection problem more than a control board problem. These thermistors have about 5vdc running through them. Since the unit worked fine when you replaced the thermistor, I suspect that the wire connection at the thermistor may be the culprit. My suggestion is to cut the wire connector out and splice the wires with new connectors and see if that will resolve the issue. Also be sure to check the wire harness from the board to the thermistor to make sure it hasn't been damaged or cut.

Hope this helps.
 

delaware74b

Premium Member
Joined
Aug 14, 2011
Messages
54
Location
Delaware
This may be slightly off topic but I have a friend who had an LG HE washer (I don't recall the model number) with the tE code. It was definitely the thermistor code but the thermistor actually tested good. It was a small amount of corrosion in the connector. I flushed it out with some electrical contact cleaner. After cleaning the connectors, no problems after 3 months and many loads of clothes.
 

gherndon

Premium Member
Joined
Dec 29, 2012
Messages
13
Location
charlotte, nc
if it's a connection problem, would i be able to get a good 14kohm reading from the connector test? or is this measuring the connection back to the controller and not all the way thru to the sensor?

i'll test the wiring before installing the replacement controller which is already on its way. any recommendation for good contact cleaners?

i will probably disassemble the harness plug at the thermistor instead of cutting it and see if i improve the contacts.

thanks, george
 

gherndon

Premium Member
Joined
Dec 29, 2012
Messages
13
Location
charlotte, nc
so, i think my best option is to get some deoxit dl100 and give that a shot (pun intended). i'll probably get the dl100 / d5 gold kit from radioshack.
 

delaware74b

Premium Member
Joined
Aug 14, 2011
Messages
54
Location
Delaware
In my situation, the thermistor on the LG washer tested within specs at room temperature. The harness also tested good, however I did see a small amount of corrosion on the pin-side of the connector. IMO, I would try cleaning the connector before cutting the connectors off both the harness and the thermistor.

The cleaner at RadioShack is a bit expensive at $20. I would recommend the Ideal Electronic Switch and Contact Cleaner #40-610 available for $9 at Lowe's. It is safe for use on plastics as well as connectors. It is flammable, so don't smoke or spray it into energized equipment.
 

gherndon

Premium Member
Joined
Dec 29, 2012
Messages
13
Location
charlotte, nc
okay, finally received the replacement part and tested this a.m. no joy.

before installing board, i cleaned contacts of each connector that i had to disassemble to prep for controller replacement. this included 4 connectors at pcb and the corresponding connectors on the pcb. i also cleaned the thermistor, door open sensor and the moisture sensor connectors while disassembled.

i tested the "cleaned" contacts using the original pcb and i still get the tE1 error.

i then replaced the controller with the new part, reassembled and still get the error. this, i think, indicates a wiring fault.

what say you, the forum?

thanks, in advance.
 
Last edited:

gherndon

Premium Member
Joined
Dec 29, 2012
Messages
13
Location
charlotte, nc
a quick question about the dielectric suggestion....never used it, but isn't it an insulator? if so, won't it inhibit a connection, which is the opposite of what i'm trying to achieve?
 

wildimaginations

Appliance Tech
Joined
Jun 13, 2011
Messages
632
Location
Danville, California
Dielectric grease is an insulator but it does reduce corrosion at the connectors.

Since you've done everything else, the only other part to replace is the wiring harness. It is very rare but I have only replaced the harness once on a tE3 error code and it was on a brand new unit.
 

gherndon

Premium Member
Joined
Dec 29, 2012
Messages
13
Location
charlotte, nc
i'm trying to get better access to the thermistor connector. how do i remove the fan from the shaft? the fan is difficult to grip and i don't want to break any fins. i have an impact wrench and might use a 1/2 to 3/8 adapter to a 13mm socket if that is advisable. what's the pro trick?
 

gherndon

Premium Member
Joined
Dec 29, 2012
Messages
13
Location
charlotte, nc
Okay. Success, if only for the moment.

I carefully disassembled the thermistor and controller 6 pin connectors and cleaned the connectors.

i reassembled and reinstalled my original contoller. The dryer passes self test and is now drying a test load.

I don't know if the problem will recur but I'm happy for now..

If it happens again I'm going to replace the wiring harness. Thanks wild and others for your help. I'm guardedly optimistic

George
 

gherndon

Premium Member
Joined
Dec 29, 2012
Messages
13
Location
charlotte, nc
sensor drying is still not what we expect. the dryer isn't getting the loads dry, contrary to the timer countdown and the what we've come to expect.

i may swap the controller to the new part and see if we get different results. i half-way tested the moisture sensor when i did the self test. i used a damp cloth and held it over the moisture sensor and the diag display went from 270ish to 170ish quickly. that's all i tested, so a proper re-test may be in order.

@wild, others, what should i test now, if i think the thermistor / controller and basic connections are good? the easy, vent obstruction went out the test window a long time ago.

thanks, george
 

gherndon

Premium Member
Joined
Dec 29, 2012
Messages
13
Location
charlotte, nc
so, another update. the dryer isn't getting as hot as it should. i tested the heater circuit and values are:

1 to 2 > 20 ohm
1 to 3 > 20 ohm
2 to 3 > 40 ohm (i'm using an analog meter)

so, service manual says replace the heater. i think i'm going to replace the heater.

all other functions are normal, and the tE1 error hasn't come back.
 
Top