Have Boat Questions? Ask a Boat Repair Expert.
Hi and thank you for your question.
This sounds like a secondary ground wire did not get reconnected when you replaced the battery. You didn't specify which Wave Runner, model or year so I cannot be more specific than that right now.
If it is a 2 stroke, you can check the engine stop switch by disconnecting the 2 wire connector that has a white wire and a black wire in it. The switch connects the white wire to the black which grounds the ignition and stops the engine. You can check for continuity to ground on the harness side of the black wire and on the switch side check from white to black, showing continuity when the button is pushed.
If you need more help, let me know but give me the model and year of your WR so I can be more specific.
Thank you for the additional information.
This definitely sounds like a grounding issue.
Check for a ground on the black wire coming out of the handlebar switch then check for the continuity through it. Something must have gotten disturbed in the process of the battery exchange, or we are dealing with a bad connection.