The high-voltage capacitor shorted and it blew the main fuse (20A) causing a loud popping sound. I replaced the capacitor the fuse and the related high-voltage diode (I think the diode was stressed during the short condition). During troubleshooting and prior to the repair I checked all the switches, the high voltage-transformer, the diode and the capacitor which had a dead short of less than 1 ohm. Thanks ApplianceParsPros.com for having these parts handy.