greenworks gpw1804 won't turn on at all, power switch does nothing. checked the outlet and it's fine.

Diagnosis

When a Greenworks GPW1804 pressure washer shows no signs of power with a verified good outlet, the issue is typically in the safety interlock circuit or a tripped thermal protector. The unit requires a specific sequence: the main power switch must be on, and the spray gun trigger must be pulled and held to complete the circuit and start the pump. A failure to power on at all indicates this circuit is not being completed, either due to user steps, a tripped internal breaker, or a fault in the switch, trigger mechanism, or wiring.

How to Fix It

Follow this exact sequence to isolate the problem:

1. Ensure the power switch is in the vertical "I" (On) position, not the "O" (Off).
2. With the unit plugged into a known-good outlet, firmly squeeze and hold the spray gun trigger. You should hear the pump motor start immediately. The unit will not activate by the power switch alone.
3. If there is still no power, locate the thermal reset button (a small red button, often near the motor housing or power cord entry). Press this button firmly to reset the internal circuit breaker.
4. With the power switch OFF, unplug the washer for 5 minutes to allow any thermal overload to cool, then plug it back in and repeat steps 1 and 2.

If That Didn't Work

The problem is likely a hardware fault. First, inspect the entire power cord for cuts, crimps, or damage, especially where it enters the machine and the gun. Next, check that the spray gun trigger moves freely and engages the safety switch inside the gun handle. If these are intact, the failure points are often the main power switch, the trigger safety switch, or the internal wiring connections. These components will require disassembly and a multimeter to test for continuity and will likely need professional repair or replacement.

Heads Up

Always connect the garden hose and turn on the water supply before applying electrical power. Running the pump dry, even for a few seconds, can cause immediate and severe damage. Never use an extension cord unless it is a heavy-duty 12-gauge cord rated for the amperage, as an undersized cord can cause motor failure.