FIXED Frigidaire Refrigerator LGUB2642LF2 Evaporator Fan error code SY EF

[BackEastDon]

Model Number

LGUB2642LF2

Brand

Frigidaire

Age

6-10 years

I have a Frigidaire Gallery with the evaporator fan error code. Quick web search, order both the control board and fan. Replaced both. Plug unit in, compressor and condenser fan turns on, evaporator fan spins for a second then nada. Fan continues to spin for a second every 30-45 seconds but compressor doesn't turn on.

A bit more searching and I find the service manual online along with the diagnostic mode. In both low and hi, the fan does the exact same thing. Put the old fan back in, same thing. Put the old control board back in, same thing. Do a pin to pin test from the plug to the control board testing continuity of the wiring. That all tests good. Got 12 volts, both old and new boards.

If I leave the fridge plugged in for about 10 minutes or so and cycle the unit on and off a couple times, the compressor and condenser fan will turn on and continue to run and the evaporator fan will do its spin for a second at a time thing. Coil is getting cold but unit displays the evaporator fan error.

I'm a former electronic repair tech and owned my own repair shop for a number of years. So I remember all too well having these kinds of days every so often. Anyone have any insights they can share cause I am kind of stumped.

 

[Jake]

What was the error code Don?

Was the original evaporator fan motor spinning up for a second then nothing at first when you got that error code? or was it just dead and not spinning at all?

Use a multimeter to check the voltage at the evaporator fan motor electrical connector and see if your getting a CONSTANT 12 Volts DC.

To volt test it: Check for 12 Volts DC to the fan between red and brown wires. If it checks ok WITH a CONSTANT 12 Volts DC and the fan motor is SPINNING UP for a second at a time, then replace the Evaporator fan motor.

Here's the evaporator fan motor for your model:
241509402 Motor


Here's the control board for your model:

Frigidaire 241996359 Board, Main Power (AP5607188) - AppliancePartsPros.com

BOARD, MAIN POWER 241996359 / AP5607188 made by Frigidaire

click.linksynergy.com

Jake

 

[BackEastDon]

Thanks for taking the time to respond. Especially on a holiday which I was not expecting.

The error code is SY EF

As I indicated, I've replaced both the board and motor. I also tested the wiring for continuity back to the board connectors for Red/W, Yel/W, Brown/W and Blue/W wires. Given your response, I also dug out a bench variable power supply and fed the old motor 12volts DC with a variable voltage to yellow. The motor spins from slow to fast as I ramp up the voltage on the yellow wire. The amperage meter on the bench power supply doesn't indicate what I'd consider much of a draw. The motor label says 220 milliamps nominal.

This unit has dual Ice Makers, top and bottom. The bottom one is already disconnected but the top is one of those with the separate evaporator fan and cooling that feeds off the compressor. Can I just unplug the top ice maker to test if something there is perhaps drawing too much current from the main board? We've not used the top ice maker in years as it has always been problematic.

I ran two test from the service manual. The compressor test #38 and evaporator fan test #15. There isn't a compressor test #1 which I think is because of the type of top icemaker. Compressor turns on and condenser fan runs but the E fan only intermittently spins ever couple seconds. The voltage is 11.9 on the red and when the fan does pulse on, the voltage jumps to about 8 volts. Unplugged I have 12.6 volts on both red and yellow.

I'm thinking what are the chances that both boards or motors are bad? I've swapped out every possible combo of new and old.

 

[BackEastDon]

The board on the left is the old one. I drilled out the melted plastic retention stubs and went through the board on my test bench with my meter, hence the screws. If I had a full schematic, this is the area I am most comfortable as to circuit analysis. With the conformal coating, it is a bit challenging to to test. I've not bench tested the new motor yet and check the current draw. Motor unplugged, I've got 13 volts.

 

[Jake]

If you got 13 Volts DC constant, then it has to be a bad fan motor.

Jake

 

[BackEastDon]

I'm guessing here that the circuit cycles looking for the tach signal. 13 volts unplugged and 11.9 volts with the motor plugged in on Red with about 9 volts on yellow when it pulses. When I bench tested the motor, it took very little voltage on the yellow to get the motor to spin and there is plenty of torque from 4 volts up. If its bad it would have to be the tach circuit on the old. Not sure yet what is up with the new as I've not tested it yet.

When I get home from work tonight I'll hook up the tach signal to the O-scope and see if there is a pulse on the tach wire. I'll also test the replacement motor and let you know. Probably going to be a pain to RMA it if bad. I'll update when I know more.

 

[BackEastDon]

Got home from work and pulled the replacement fan out to bench test it. When I went to connect the power supply, I noticed the blue wire terminal on the molex type plug wasn't fully seated and the connector was pushed back a bit. Pried out the rubber seal and used a small tweaker to seat the pin. Connected it back up without even bench testing and the evaporator fan came right on when I plugged the fridge back in. Put it all back together and it has been running for about 10 minutes. I'm going to leave it run for a few hours and will check in later to update.

 

[BackEastDon]

A couple hours later and fridge is almost down to set temperatures. Will run overnight before transferring any food back to it.

Thanks for the help. Was about to just give up but would hate to be defeated by a fan motor circuit.

 

[Jake]

When I went to connect the power supply, I noticed the blue wire terminal on the molex type plug wasn't fully seated and the connector was pushed back a bit. Pried out the rubber seal and used a small tweaker to seat the pin. Connected it back up without even bench testing and the evaporator fan came right on when I plugged the fridge back in. Put it all back together and it has been running for about 10 minutes.

Excellent Don, good find.

Thanks for the update!

Jake