LG CineBeam Al ThinQ HU710PW Owner's Manual page 147

I cannot turn the projector on with the remote control.
• Please make sure your projector power plug is correctly connected to the outlet.
•
Replace the batteries in the remote control. (Use alkaline batteries.)
• Check whether there are any obstacles in front of the projector's remote control
sensor. Sound bars or other obstacles placed in front of the projector's lower
receiver may obstruct IR signal reception.
The power turns off suddenly.
• Make sure [Power Off Timer] is set.
•
There is also a chance that the internal protection circuitry has activated because
the internal temperature of the product has risen unusually or excessively.
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