How to Fix / Troubleshooting

Safety First: Disconnect power before removing any panels or touching wiring.

OP means the control detects an open circuit from one of the temperature sensors.

Step 1 – Identify which sensor: Consult the tech sheet (often behind the kick plate or rear panel) to determine whether OP refers to the freezer, evaporator, or ambient sensor on your specific model.
Step 2 – Inspect sensor connection: Locate the indicated sensor and verify the connector is fully seated. Look for broken wires or corrosion.
Step 3 – Test continuity: With the sensor disconnected, measure resistance across the sensor leads. If the meter reads OL (open), the sensor is bad and must be replaced.
Step 4 – Check harness to board: If the sensor tests good, check continuity from the sensor connector to the control board pins. Repair any open wires or damaged connectors.
Step 5 – Clear code: Restore power and see if the OP code clears. If not, the control board input may be defective and require replacement.

Display shows OP and temperature reading is missing or shows dashes; freezer may run continuously or shut down.

Possible Causes