Vestel 17ips12 Schematic !!top!!

int main(void) init_pwm();

| Symptom | Likely Fault | Check / Replace | |-----------------------------|----------------------------------|-------------------------------------------| | No power, no 5VSB | Burned A6069H (U2) or fusible resistor R22 (1–2.2Ω) | Check R22, replace U2, check D11, D12 | | 5VSB ok, no 12V / main voltages | PS_ON signal missing or SSC3S910 (U1) failed | Confirm PS_ON >2V; check U1, optocoupler U5 | | Backlight flashes then off | LED overvoltage / open string | Measure LED+ voltage – should rise then drop – replace LED strips | | Backlight very dim | Failed MAP3204 (U3) or bad dimming circuit | Check U3, R52/R53, D25, Q8 | | Whining noise from PSU | Bad primary capacitor C5 (150µF/450V) or dry joints on transformer T1 | Replace C5, resolder T1 | vestel 17ips12 schematic

The mainboard must send a "Power_On" or "STBY" signal back to the 17IPS12 to wake it from sleep mode. If this logic signal never arrives from the mainboard, the power supply will remain idle. Conclusion int main(void) init_pwm(); | Symptom | Likely Fault