I replaced the batteries two years ago with eneloop pro AAA batteries and it worked well for 1.5 yrs. Then it started to shut down after about 10 minutes of use.

I opened the unit and tested old batteries using ZTS MBT-1. Oddly, it showed 80%. Shaver didn’t run and would blink orange.

Regardless. I put 2 new batteries in it, and exactly same behavior!

Did another test. Disengaged the trimmer blade and let the motor run to see when it shuts off. It ran for solid 2 hours before it shut off, but still the batteries were not depleted (about 60%). I did this test to make sure that there is no timer on the chip that’s causing it.

Then followed the advice that batteries should be depleted when installed. Took out the batteries, depleted all juice in them. Installed and let the shaver charge. Took out the batteries, charged at 100%. Depleted again and put them back to charge. The overall behavior very slightly improved, but in the end, shaver shuts down at 80% charge. Blades are lubed and running smoothly.

Any Ideas?