JB4 Mobile Troubleshooting

Try disconnecting then reconnecting the DB9 connector. You can also try *SLIGHTLY* bending the 3 or 4 DB9 pins in the Connect Kit's connector towards the middle. Video Demo.

If that doesn't work it's either an issue with the Connect Kit or a problem with the JB4 Master Chip. In order to test this you'll need access to another Connect Kit or BMS Data Cable. If you're unable to find either of these you're welcome to send your kit in for diagnostics. Email into support@jb4connectkit.com and let us know you're interested in having your kit tested and you've already performed the appropriate diagnostic steps.

You'll need to include a copy of your original purchase receipt for the Connect Kit.

There is an issue with your OBDII/CANbus wire installation. For further assistance, email support@burgertuning.com.

VW Passat/Jetta Owners - Set FUD to 1 as a test

If you are using a JB4 Connect Kit:
You have an incorrect setting toggled. Please look at the "OTG Data Cable Connection" field near the bottom of the Connection Settings page (accessed by clicking the Settings Tab then Advanced).

If you are using an OTG Cable:
1) Attach the OTG cable (*by itself) to your device then attach the BMS Data cable and try connecting again.

2) Download USB Device Info from the Play Store.
Open that app.
Connect the cable.
Does that app show anything connected?

If not, then there is an issue with your device, OTG cable, or BMS Data cable. If something does appear and you still have issues in JB4 Mobile, email into support@jb4connectkit.com and let us know you've performed the diagnostics for this specific error message.

1) Ensure the Connect Kit is as far away as possible from nearby batteries and metals. If using a metal JB4 enclosure do not mount/attach the Connect Kit to the enclosure as this can reduce bluetooth range.

2) Holding the phone next to the Connect Kit under the hood can help reduce issues due to signal strength.

3) Locking doors and waiting 5 min for ECU to reset, and restarting phone, can sometimes help.

4) Increasing Upload Timeout setting in the app to a higher number, or going up to 25, can be helpful. This setting is found directly above the 'Update' button in the Firmware Update page.

5) If all else fails and your Connect Kit has the separate blue power wire attached using a posi-tap connection to the JB4 harness, disconnecting the blue wire and *temporarily* attaching it to 12v on the vehicles battery rail will increase power to the Connect Kit and may allow the update to complete.

Make sure the device ACTUALLY supports Bluetooth 4.0 or higher. If it says it only supports calls and audio, odds are the unit is using a sub-par BT radio and simply will not work. Your only option is to use the BMS Data Cable and an appropriate OTG adapter.

If your 'Send' button is grayed out (or hitting 'Email' just does nothing) and you're unable to email logs, this means you don't have an email account setup with the DEFAULT Mail.app on your device. Note that the default Mail.app is NOT (I repeat NOT) the Gmail app, the Ymail app, or any other email app. It should be a blue icon with a white envelope.