Look for bulging or leaking electrolytic capacitors on the secondary side. Even if they are not bulging, high Equivalent Series Resistance (ESR) can cause voltage ripples that trip the protection circuit. 2. Symptom: Completely Dead, No Power LED Probable Cause: Blown main fuse due to a short circuit.

This section takes the low-voltage DC from the SMPS secondary side and steps it up to high-voltage AC (often exceeding 600V AC) to power the monitor's CCFL backlight tubes.

At the AC input, you will find a fuse, a varistor (MOV) for surge protection, and a network of inductors and X/Y capacitors forming an EMI filter. If the monitor is completely dead with no standby light, this is the first area to check. A blown fuse here almost always points to a shorted bridge rectifier or a shorted main switching MOSFET. The Feedback Loop