To program a Motorola remote control for your Sharp 42-inch TV, try using the code search feature on the remote. First, turn on your TV, then press and hold the "TV" button until the LED lights up. Next, enter the code "001" or "002" (common codes for Sharp TVs), and press the "Enter" button. If this doesn't work, consult the remote's user manual for a complete list of codes specific to your model.