Display shows SY CF; refrigerator may not cool or may behave erratically.

Safety first: Disconnect power before touching any internal components. Do not attempt board-level repairs; replacing the board as a unit is the safe method.

Steps to resolve:

• Power reset: Unplug the refrigerator or switch off the breaker for 10 minutes, then restore power. Observe whether the code reappears.
• Check for other symptoms: Note if the compressor, fans, and interior lights operate. If multiple functions are dead, the control is likely failing.
• Inspect for visible damage: Remove the rear control cover (with power off) and look for burnt spots, bulging capacitors, or a burnt smell on the board.

If SY CF returns after a reset and the board shows signs of damage, the main control board must be replaced. This is a complex repair that should be performed by a qualified technician to ensure correct part selection and safe installation.