Frigidaire · Refrigerator Moderate

3 SY — Evaporator Sensor Open

Open-circuit reading on the evaporator thermistor. Board cannot verify coil temperature during defrost.

Keep using it?
Yes, with caution
DIY difficulty
Moderate
Verified against
frigidaire.com ↗

How to fix it

  1. Unplug refrigerator and access the freezer evaporator coil.
  2. Inspect and reseat sensor connector.
  3. Ohm sensor — replace if open.
  4. Check wiring continuity back to the main board.
  5. Replace main board if input is dead.

Why it happens

Typical signs: 3 SY shown · Excessive frost on evaporator · Long defrost cycles or repeated defrost · Warm freezer compartment

  • Open evaporator thermistor Element broken.
  • Severed sensor wire Cut by defrost ice or sharp panel edge.
  • Loose connector Disconnected at the main board.

Parts you may need

If diagnosis points to a failed part, these are the common replacements. As an Amazon Associate we earn from qualifying purchases.

  • Evaporator thermistor Common replacement
    Amazon →

More Frigidaire refrigerator codes

1F 1F — Ice Maker Fault 1 SH 1 SH — Fresh Food Sensor Shorted 1 SY 1 SY — Fresh Food Sensor Open 2 SH 2 SH — Freezer Sensor Shorted 3 SH 3 SH — Temperature Sensor Short 4 SY 4 SY — Ambient / Defrost Sensor Open

All Frigidaire codes → All refrigerator codes →

Always unplug an appliance before servicing it. This guide is for informational purposes and is not a substitute for a qualified technician. Verified against manufacturer documentation: frigidaire.com.