Vestel 17IPS12 Schematic: A Critical Guide for Power Supply Repair
Optocoupler: IC903 (PC817 or SFH615). The schematic shows the LED side (connected to secondary 5V or 12V) and the transistor side (feeding back to the primary PWM's FB pin).
Voltage reference: IC904 (TL431). This is a precision shunt regulator. The R/C network around it determines the exact output voltage.
PS_ON
With the schematic, you can measure reference voltages: 5V_SB at TP801, 12V at TP803, 24V at TP805. You can also isolate the power supply from the main board by shorting the line (usually pin 2 or 3 of CN802) to 5V_SB via a 1kΩ resistor.
Warning:
Many websites claim to offer free schematics but provide low-resolution images, malware, or incomplete diagrams. Use the following reliable methods: vestel 17ips12 schematic