Hello.
I am replacing a bathroom light/exhaust fan. The previous llight had no ground wire and the wire leading to the unit has no ground. The new unit does.
How do I ground the unit?
Thanks for your time
E

If the box is metal, the wiring method may be BX (AKA AC) cable, and the box is the ground. You can use a voltage tester, measure across the hot wire and box, if you see 120 volts, then the box will suffice as a ground.

Otherwise, you may need to install a GFI device to protect the fan/light.