Motor Vehicle Maintenance & Repair Stack Exchange is a question and answer site for mechanics and DIY enthusiast owners of cars, trucks, and motorcycles. It only takes a minute to sign up.
Sign up to join this community
Current I am working on OBDII. While in bluetooth discovery to connect obd, How I determine which device is obd and which device is normal bluetooth device.Because I want auto connect my app with obd.
Is there any common characteristic of obd device which help me to determine this is OBD device.
Any help is appreciate.
Each bluetooth device has a unique 48 bit address and a device name (up to 248 bytes). The name is usually shown when doing a bluetooth scan with a mobile device. The only way you can tell the bluetooth device is an OBD scanner is by checking it's name or address, the fact that it's an OBD scanner does not give it any special properties from the point of view of a mobile device.
To put it simply, you do a bluetooth scan and check the found device names. The name usually reveals that it's an OBD scanner, but it may differ depending on the manufacturer. If you want to use it with one specific OBD scanner that you have - just find and store it's name or address.
If your software (app) only shows addresses and not meaningful names and you have access to another car, try it there and see which address is present at both locations. Alternatively, you could power up your scanner directly from a loose 12V battery, away from any other Bluetooth sources by connecting pin 16 to positive and pin 4 to negative. You should be able to complete the pairing away from the car. Remember that you must pair your device in Android before trying to connect in your app.
The easiest way is to first check whether the device supports the serial (rfcomm) profile. If not, it's not an OBD2 device. The second step is connecting to it and sending it some AT commands, e.g. ATI (send identification). If it responds, you can even send PIDs to find out whether it's connected to an actual car.
