Pairing... the most frequent problem area.
The next most frequent is that the device paired Ok,
but the connection between the app and the device
is frequently lost, and re-connection is difficult.
1. With the app closed, use the Android system Settings, and tap Bluetooth
to enter the BT management, ready to turn Bluetooth On.
2. "Start" the car and let it get Ready to drive. Turn Bluetooth On in your phone.
3. Then, quickly plug the ELM327 device into the car's OBD connector.
Assuming no BT devices have been discovered or paired, the phone searches
for discoverable BT devices. Otherwise, ask the phone to search.
4. When the phone discovers a new (new MAC address) ELM327-type Bluetooth
device (often called OBDII), it appears on a list, as not yet paired.
Quickly tap the item on the list, enter the pairing code (most often 1234, rarely 0000,
and very rarely 6789), and attempt to pair with the ELM327 device.
If successful, the listing will show paired, but not connected.
If not successful, try to enter the pairing code again.
5. If the second try fails, unplug the ELM327 device dongle and start step 3 again.
Sometimes the pairing must be done within the first few (maybe 30) seconds
after the dongle is plugged in.
6. Successfully paired, you can turn your phone's Bluetooth Off, since
the LEAF Battery app will turn it On when needed.
You can now run the LEAF Battery app and you should see live data
in just a few seconds.
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Notes: If you have trouble, try to get with another LEAF Battery app user,
and see their system working on their car, try their system on your car,
try your phone with their ELM327 device, and finally try your ELM327 device again.
The most often problem is a stubborn ELM327-type clone device, even an
"identical" one from the same supplier. Sometimes you will get different
circuitry inside the device, or different firmware, in devices from the same vendor.
Clone firmware 1.5 is to be preferred, I think.
Genuine ELM327 devices have 1.4b as their latest version, I think.