Sub-Zero Refrigerator Error Code Su

The Su code on a Sub-Zero refrigerator indicates that the blue wire of the display cable is unhooked or faulty. This wire is part of the circuit connecting the control board to the display panel, and when it loses connection, the top interior lights also turn off. The error is a wiring fault, not a compressor or cooling system failure.

A power reset will not permanently clear the Su error code if the underlying wiring fault is still present. The code will return as soon as the refrigerator powers back on and the control board detects the open or faulty blue wire circuit. The wiring issue must be physically repaired first.

If the fix is simply reseating a loose connector, a service call alone may resolve it, typically ranging from $100 to $200 depending on your location. If the display cable assembly needs to be replaced, parts and labor combined generally range from $150 to $400 or more, depending on the specific model and the extent of the repair.

If the blue wire connector has simply come loose, reseating it is a straightforward repair that a handy homeowner can attempt after unplugging the refrigerator. However, if the wire is broken or the cable assembly needs replacement, routing the cable correctly through the cabinet and accessing the control board connections is more involved and typically best handled by a qualified technician.

The Su fault is a display and lighting circuit issue, not a refrigeration system failure, so your compressor and cooling should continue to operate normally. Your food should remain safe during the repair process. The primary symptom you will notice besides the error code is that your top interior lights will be off.