I have a RY40001 40V strimmer, which when it works properly is great!

However it has developed a problem. When I clutch the upper control handle as one must do to start the strimmer, then pull up on the lower control handle (trigger), the strimmer operates normally sometimes, but other times it runs for 2-3 seconds, then stops. If I release the trigger, the process repeats. I can do that for either 2, 3, 4, or maybe 5 times, then no response at all.

If I remove the battery, then replace it, the whole process starts all over again.

Sometimes when it will not start in the normal strimming position, I can raise the cutting end high in the air, and the burst process starts again.

I can imagine three possible problems: (1) something is wrong with the battery, ( 2) something is wrong with the battery/battery holder contacts, or (3) there is a loose wire inside the control lever/trigger handle.

Has anyone had a similar problem or otherwise have some idea how I can isolate the problem?