Where does Real Dash get its battery voltage information from?
where this information is not very accurate
It should be getting voltage from the ecu or I believe measuring the current from the device. Similar to how some car charger sockets show voltage once plugged in.
If its the latter, I’ve been told it’s inefficent due to other devices drawing power and such from it. Something like that is what my mechanic told.
If you wanted to get a true voltage reading you’d have to get it straight from the battery I believe. That I wouldn’t know how to do, assuming it’d need its own sensor.
Edit: p.s newer vehicles also control the voltage and can drop below the usualy 12V i think. Honda has something like that where my cars will ocasionally drop below a certain voltage due to regulator but it’ll go back up once i start giving gas.
I say how to configure in the add gauge, I create a text gauge and change it to 0.00 and then I go to value input and select the data source which would be battery voltage, is this configuration correct or would there be another way to show the battery display
By chance it to 0 what do you mean? If you put static text on the text gauge then it won’t show the voltage. You should just make a text gauge and select the input to be the battery voltage. From there you can adjust levels and colors.
Edit: if you want another way you can make an image gauge for the battery voltage and change the levels on it. So when it’s outside of the normal range it’ll glow yellow or red.
If you are using OBD2 connection to your vehicle, the battery voltage is requested with ‘ATRV’ command. That returns the voltage as the OBD2 adapter sees it and request is never sent to the vehicle. This is done because its faster and on many vehicles ECU voltage is a custom PID.
But many cheap OBD2 adapters do not have voltage calibrated properly. And there may be an deviation on the reading. It is possible to calibrate your OBD2 adapter, but its somewhat complicated and not recommended for beginners.
How to calibrate the OBD2 battery voltage - Connectivity / OBD2 - RealDash Forum