Chosen Solution

My Garmin Nuvi 65LM won’t turn on and I do not know whether it is the charger or the battery at fault. Is there any way of finding out without having to buy replacements for both?

You can use a standard MicroUSB phone charger to see if the Garmin charges.

Most chargers will have a light to show whether it is charging or not. If you are using a non-Garmin produced charger, an error message could appear stating that charger will not work.