Kenmore Washer Error Code E91: Communication Error... | appliancefaults.com

Technical Background:

error code E91 indicates a communication failure between the user interface (UI) board and the main control board. The UI board sends signals to the main control board to initiate and control the wash cycles. This communication typically happens via a low voltage DC circuit. If the main control board does not receive the correct signals, it will generate the E91 error. Voltage paths are usually 5V DC or 12V DC.

Symptoms:

The Kenmore washer displays error code E91 on the control panel and may not start or operate correctly. The user interface may be unresponsive or display incorrect information.

Possible Causes:

Loose wire harness connection between the UI board and main control board.
Damaged wire harness between the UI board and main control board.
Faulty UI (User Interface) board.
Failed main control board.
Power surge damaged the boards.

Solution:

1

Unplug the washer from the 120V AC power outlet.
2

Locate and inspect the wire harness connecting the UI board to the main control board for any signs of damage, corrosion, or loose connections. Reseat the connectors firmly.
3

Using a multimeter, check the continuity of each wire in the harness. Replace the harness if any wires are broken or shorted.
4

Restore power to the washer. If the error persists, proceed to test the UI board.
5

Unplug the washer again. Remove the UI board and inspect it for any visible signs of damage, such as burned components or swollen capacitors.
6

If no damage is visible, replace the UI board with a new one.
7

Plug the washer back in. If the error code is still present, replace the main control board.

Safety Warning:

Always disconnect the power supply before working on the washer. Use appropriate lockout/tagout (LOTO) procedures to prevent accidental energization. The main control board contains high voltage components that can cause serious injury or death. Use extreme caution when working around these components.

Prevention:

Periodically inspect the wire harnesses for any signs of damage. Use a surge protector to protect the washer from power surges. Avoid overloading the washer.

Expert Tip:

Some Kenmore washers have a diagnostic mode that can provide more detailed information about the error. Consult the service manual for instructions on how to enter diagnostic mode. Sometimes repeatedly opening and closing the washer door (6 times in 12 seconds) can reset the UI.

Frequently Asked Questions

•What voltage should I expect to see on the communication wires between the UI and main board?

Typically, you should expect to see 5V DC or 12V DC on the communication wires. Refer to the wiring diagram for the specific voltage.

•How do I access the main control board on this Kenmore washer model?

The main control board is usually located behind the rear access panel of the washer. You may need to remove the top panel first to gain access.

•Can I use a universal UI board as a replacement, or do I need the exact Kenmore part?

It is highly recommended to use the exact Kenmore replacement part for the UI board. Universal boards may not be compatible and could cause further issues.

Kenmore Washer Error Code E91: Communication Error Troubleshooting

Technical Background:

Symptoms:

Possible Causes:

Solution:

Safety Warning:

Prevention:

Expert Tip:

Frequently Asked Questions

•What voltage should I expect to see on the communication wires between the UI and main board?

•How do I access the main control board on this Kenmore washer model?

•Can I use a universal UI board as a replacement, or do I need the exact Kenmore part?

Related questions

Technical Background:

Symptoms:

Possible Causes:

Solution:

Safety Warning:

Prevention:

Expert Tip: