Press and hold the Lock and Unlock buttons together for 3 to 5 seconds
Press and hold the Temp Up and Temp Down buttons together for 3 to 5 seconds
Press and hold the Mode and Fan buttons together for 3 to 5 seconds
Press and hold the Plus and Minus buttons together for 3 to 5 seconds
Press the Child Lock button if your remote has one
Remove the batteries for 30 seconds, then reinsert them
Check the remote display for the lock icon and repeat the same button combination if needed
Refer to the remote model label for the exact lock key combination