Yeah, this one's common. You're overloading the circuit or using the wrong setup.
First, check the fuse or circuit breaker you're blowing. It needs a higher amp rating than the amp consumption of the pressure washer. You must use a fuse with a higher amp rating than the machine draws.
Second, lose the extension cord if you're using one. Try the unit plugged directly into a wall outlet. A defective or undersized extension cord is a prime suspect for blowing fuses.
Also, switch off any other machines (like a fridge, shop vac, or lights) that are running on the same circuit before you start the pressure washer. It needs the full capacity of that circuit.
IF THAT DIDN'T WORK: There might be an issue with the mains voltage being incorrect for the machine. Check that your outlet voltage matches the specification on the model tag of the pressure washer. A significant voltage drop can cause this.