It is not your relay. Mine did the same and the problem is the resistor that drive it goes short so the relay clatters as the circuit is trying to control it. The actual fault is the 78p153sp driver. You can change the transistor, a pnp will do the trick but the driver is dead. I'm currently looking for this IC and they're hard to find, cheap Chinese tat. So instead I'll likely fit a temp sensor that detects when the cooling coils reach about 4deg and switch the fridge off because shorting the relay will just cause the cooling to stay on and you'll get ice, it needs to cool, collect moisture, switch off, warm up and dump the moisture...crude but it works. This unit is worth saving.

My unit is clicking due to fault with motherboard. friend local agent said replacements not available but said he thought the relay had failed. friend is going to replace the relay for me. there are threads on line that suggest that this will fix the problem. we will see!?