Optoma H79 Service Manual page 38

5. Turn on the Power Switch of H79.
Note : First, the Power LED shows blue light, then wait a moment the Lamp
LED shows red light and the Power LED flash blue light simultaneously.
6. After all files are downloaded, turn off Power Switch, then power on and enter
the service mode to check the F/W version.
Notice : Press the "RESYNC", "SOURCE", "ENTER" button at the same time to
enter the service mode.
5-4 H79