Frigidaire Refrigerator Error Code Er CO

Er CO indicates a communication error between the main PCB's microcontroller and the display board's microcontroller. The two boards communicate over a low-voltage signal line, and when that connection is lost or corrupted, the refrigerator displays this fault code. The most common starting point for diagnosis is checking the CON101 connector on the display PWB and measuring voltage at pins 4 and 5.

A power reset by unplugging the refrigerator for a few minutes may temporarily clear the code, but it will return if the underlying communication problem is not resolved. If reseating the CON101 connector fixes the loose connection, the code should not return after a reset. A persistent Er CO code after a reset points to a wiring or board-level fault that requires further diagnosis.

If the fix is simply reseating or cleaning the CON101 connector, there may be no parts cost at all. A replacement wiring harness typically runs in the range of $20 to $60 in parts. A new display board generally costs between $80 and $200, and a main PCB replacement can range from $100 to $300 or more depending on the model. Labor costs from a technician will add to these figures.

In many cases, yes. Start by unplugging the refrigerator and inspecting the CON101 connector on the display board to make sure it is firmly seated and the pins are not corroded or bent. If the connector looks secure, use a multimeter to check for 0V or 5V at pins 4 and 5 of CON101 after restoring power. If the readings are abnormal after confirming the connector is good, a wiring harness or board replacement may be needed, which is more involved but still possible for a skilled DIYer.

An Er CO error means the main control board and display panel are not communicating properly, which can affect the reliability of temperature control and user input functions. It is not advisable to rely on the refrigerator for extended periods while this fault is active, especially for storing medications or perishables that require precise temperature management. Address the fault as soon as possible to avoid potential food safety risks.