A: There are below portable issues if the GPS tracker is not located:
(1)The installation environment is not good, like there is special film on the top of the vehicle or there is metal covered above the installation position or the installation position is much hidden.
(2)The environment around the vehicle is not good, like there is many tall building or dense trees around the car or there is something disturbs the GPS signal around the vehicle.
(3)The signal of GPS tracker is also related with the weather, the GPS signal is not good if in the rainy day.
Please take some photos to show us where is the OBD tracker installed in this vehicle? Also please confirm above points.

A: You can know the GPS location status from the GPS led, green led solid on means searching the GPS signal, green led blinking(on 1 second, off 1 second) means the GPS is located, green led is off means GPS is off.

A: The data calculation method and the origin of the mileage calculated by OBD tracker and from the odometer are different, the OBD tracker read the vehicle speed/mileage from the ECU and the mileage from the odometer is calculated by the speed sensor, so the result is different, it’s normal if the difference is less than 5%.