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Disconnect power from the ACU
Hold down the ADMIN BUTTON for 15 seconds
While still holding down the ADMIN button, reconnect the power, and continue to hold the button for another 15 seconds. If resetting a 4 Door Controller, you should see two POWER LEDs light up in the top left corner.
Wait 15 minutes before provisioning the ACU
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ADMIN button on 4 Door Controller (left) and
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ADMIN button on Core Board (right)