The school where my kids learn have some old (10 year old) projectors and they are starting to fail. I took down one of them (a BENQ MX518 model) and tried to fix it. Its lamp didn't start and it showed two red leds: Lamp and Temp: I replaced the lamp with a new one, but when I tried to start it it would still show both leds on and wouldn't power on the lamp. So, I took it down and tore it apart (in addition to the screws, there were some plastic clips that need opening). Inside, as expected, was a thick layer of dust: The radiators were full of dust, but the fans still worked. The dust worked as an insulator, preventing components from cooling. This is not a fan, but a speaker! Thankfully, the capacitors on board looked fine, without leaks The components below seem to have been fixed in place with hot glue, so that they don't vibrate: After a thorough cleanup (with a vacuum, alcohol and cotton swab) most of the dust was removed and I could test the lamp once more. Take c...