If standby light is red, the issue area to check first is the power supply board. These did suffer from poor soldering quality control, and could be the problem, as can failed capacitors. Look for bulging capacitors on power supply board and on inverter board. Any that appear bulged should be replaced, as well as those in close proximity.

Replacement boards are available through various vendors and Ebay if you are not wanting to spend the time at the board level..