Replace the Faulty SM-S-105DM Relay

Safety Warning: Ensure the device is completely disconnected from all electrical power sources before beginning. Use caution when handling live circuits.

1. Use a soldering iron and desoldering pump to remove the faulty SM-S-105DM relay from the circuit board.
2. Clean the through-holes on the PCB to ensure a clear path for the new component.
3. Insert a new, identical SM-S-105DM relay, ensuring the pin orientation matches the original configuration.
4. Solder the pins to the board, ensuring clean, solid joints without bridges.
5. Verify the fix by testing for 5V DC control signal input and confirming the relay toggles correctly under normal operating conditions.

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