Frigidaire Dishwasher Error Code i91

The i91 code means the dishwasher's main control board has failed an internal checksum verification of its firmware data. This is a self-diagnostic fault that prevents any wash cycle from starting. The board is essentially detecting that its stored program data does not match what it expects to find. A power cycle is the first recommended step to attempt clearing the fault.

Start by turning the dishwasher completely off and back on again to force the control board to rerun its self-check. If the error clears, the cause was likely a transient power issue. If the i91 code returns after the reset, the main control board has a permanent firmware or hardware fault and will need to be replaced by a qualified technician.

If a power cycle resolves the error, there is no cost involved. If the main control board needs to be replaced, parts typically range from $100 to $250 depending on the specific model, with professional labor adding another $75 to $150. Total repair costs for a control board replacement generally fall between $175 and $400.

A power reset is the first recommended diagnostic step and may clear the i91 error if it was caused by a temporary power fluctuation. Turn the dishwasher off, wait at least one minute, then turn it back on to allow the control board to reinitialize. If the error returns after a full reset, the fault is likely permanent and the control board will need to be replaced.

The i91 error code actually prevents the dishwasher from starting any wash cycle, so the appliance will not operate while the fault is active. There is no immediate safety hazard, but the dishwasher is non-functional until the error is resolved. Do not attempt to bypass the control board to force a cycle to run.