1. Check the antenna connection: Make sure that the antenna is properly connected to the radio.
2. Check the fuses: Check the fuses labeled "RADIO" and "ACC" in your fuse box. If any of these fuses are blown, replace them with new fuses of the same amperage.
3. Reset the radio: Press and hold the "POWER" button on the radio for at least 5 seconds. This will reset the radio and may clear the Error 3 message.
4. Update the radio software: If the above steps do not work, you may need to update the radio software. You can do this by downloading the latest software update from the Honda website and installing it on your radio.
5. Contact the dealer: If none of these solutions work, you may need to contact your local Honda dealer for further assistance.