If the schematic is working, you should see a stable 12.2V to 12.3V on the yellow wires. Safety and Repair Precautions
Short the green wire (PS_ON) to any black wire (Ground). ps42419ha schematic work
The PS-4241-9HA is a switching power supply designed to convert 100-240V AC input into stable DC voltages (primarily +12V). Its work can be divided into several functional blocks: If the schematic is working, you should see a stable 12
Always use a discharge tool (like a high-wattage resistor) on the primary capacitor before touching the board. Its work can be divided into several functional
Measure the voltage on the purple and green wires. You should see roughly 12V (standby) on the purple wire and a low logic voltage (approx. 4.4V) on the green wire.
Incoming AC passes through a fuse and an EMI filter to remove noise. A bridge rectifier then converts it to high-voltage DC (around 145V–160V depending on load and region).
Repairs typically center on the standby voltage circuit, which is the most frequent source of failure in the PS-4241-9HA.