Diagnosis
The G4 has an IPX4 rating. It can handle light rain and splashes, but not submersion or high-pressure spray.
How to Fix It
Use a damp cloth only. Wipe down the deck, stem, and wheels. Never spray water directly at the deck, display, or charging port. Dry it thoroughly with a towel. Let it air dry completely before charging.
If That Didn't Work
If water did get into the deck, open it and inspect for pooling. Dry all components with compressed air or a fan. Check connectors for corrosion.
Heads Up
The bearings in the wheels and folding mechanism are not fully sealed. Water intrusion there causes rust and grinding. Lubricate these points with a light grease after cleaning.