DS18B20 faulty?

Using a DS18B20 and the signal wire is shorted with ground on the multimeter.
Connected to a MC and i get can’t find device.

Hey David,

First off, which MicroController are you using?

Secondly, with that specific sensor, you can use it in parasite power mode, meaning that you only need two wires: ground and data, no need for pullup resistor for the data.

VDD must be grounded for operation in parasite power mode. DS18B20 needs strong pull-up on the data line in this mode. If you are using a Raspberry Pi, this is achievable by issuing this commands:

sudo modprobe w1-gpio pullup=1
sudo modprobe w1-therm strong_pullup=1

Using a itsybitsy m4 for the MC. Coding with arduino ide