After power outage the fridge was displaying codes SY and EF I have Frigidaire model number FGHS2365KF1. Any thoughts?????

Call a local repair service. Possibly a bad control board that we DIYER's can not change out if we could even get one.

Hello Brian Watkins,

Not seriously able to BEGIN to help without
any MODEL NUMBER... any chance you could
REPOST your question... (comment or EDIT it in?? ).

I have not been doing any answers on this site
due to the MASSIVE SPAM and CYBER ATTACKS
but I thought is was time to TRY

One of my FAVORITE sites for VIDEO procedures...
Give it a look (still requires MODEL NUMBER).

Search Over 2 1 Million Appliance Parts

look here
code SY EF Google Search

Your evaporator fan is not spinning.

Check to make sure there isn't any ice build up jamming up the fan. If there isn't then it's either the evaporator fan, or the main board.

For instructions on getting a new solenoid valve as well as various other parts, check the parts manual for the refrigerator:
Frigidaire refrigerator parts manual

Good Morning Friend,

I understand you are receiving an "SY EF" code on your Frigidaire refrigerator, model# FRS3R5EMB. The "SY EF" code stands for system error with the evaporator fan. This possibly means that there is something going on with your evaporator fan or it could possibly be a false error code. . I suggest resetting your appliance, by either unplugging it or shutting the power off at your home's circuit breaker, for 3-5 minutes. I ask that you please follow up with a comment on the post, at your convenience, to advise if further troubleshooting is needed or if your appliances status has changed successfully.

-Best Regards-
WP

Good Afternoon Friend,

I understand you are receiving an SY EF code on your Frigidaire refrigerator, model# FGUN2642LF. This code states there is a system error code that deals with the evaporator fan. This could also be a possible false error code. I suggest you reset your appliance, by either unplugging it or shutting the power off at your home's circuit breaker, for 3-5 minutes. Once power is restored, you will need to press the "Mute Sounds" button to stop the power failure alert. I ask that you please follow up with a comment on the post, at your convenience, to advise if further troubleshooting is needed or if your refrigerator status has changed successfully. Hope this is helpful.

-Best Regards-

WP

Hello Angela Clark - Typically error code SY CF indicates that the refrigerator has detected a communication failure after power up. Contact a professional to move forward accurately. The wiring between the main control board and user interface board will need to be check and diagnose. Depending on the diagnoses the main control board may need replacing.