Review on 🔋 KONNWEI KW208 12V Car Battery Tester: Reliable Digital Auto Battery Analyzer for Car, Truck, Motorcycle, Boat, and More by Isaac Simpson

I mainly use this to test 12v AGM batteries. This worked well for most batteries and most car batteries, but ran into a problem. When I applied a slightly overcharged 12 volt battery that charged to 13.3 volts it showed -0.24v and got stuck there and hasn't tested the others since. Thinking I had a broken one, I ordered the same one again. The new one did exactly the same thing. After a few days the tester worked again but was afraid to test batteries over 13.3V. Since the charging system is also to be tested, this means that it must be able to withstand more than 14 V. I may have received 2 defective units, I don't know, but I can return a new one. I can't return the first one as it's been 3 months, but most likely I'll be able to test most of the battery. First you need to attach a voltmeter so that it does not exceed 13V. It shouldn't work like that. Check the battery before using the tester! LAUGH OUT LOUD!