Acer PD525 Service Manual page 56

A. Remote Control No Function.
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Check the Laser function of Remote control.
(Replace the battery if there is no Laser output from the Remote control.)
Use a known Remote control for the function test.
(Replace the Remote control if the new Remote control works fine
with the Unit.)
Check the Main board if the Unit works fine with a known good
Remote control.
Chapter 4