DIY Trailer light tester - review and how to build one.

Build your own trailer light tester which is powered by a standard drill battery. Helps with checking lights without a vehicle or diagnosing issues without risking an annoying to change fuse on a vehicle.

[@chrisfranklin1535]

What type voltage indicator did you use?

[@WarriorWoodshop]

Comimark 1Pcs XH-M609 DC6-60V Battery Low Voltage Disconnect Protect Undervoltage Module, I WOULD NOT RECOMMEND. After 6 months, it is not working properly.