Quick answer
- The Onkyo TX NR646 may display error codes due to HDMI or connectivity issues.
- Common symptoms include no sound, video dropouts, or the receiver not powering on.
- Quick checks include verifying cable connections and ensuring the receiver is updated.
- If the issue persists, follow the step-by-step fix outlined below.
Symptoms
When your Onkyo TX NR646 displays an error code, you may experience several issues:
- No audio output from connected devices.
- Video signal interruptions or black screens.
- The receiver not responding to remote commands.
- The receiver may power off unexpectedly.
Quick checks
Before diving into more complex troubleshooting, perform these quick checks:
- Ensure all HDMI cables are securely connected.
- Check that the receiver is set to the correct input source.
- Restart the receiver by unplugging it from the power source for 30 seconds.
- Verify that your HDMI cables are certified for high-speed use. Consider using a Certified Ultra High Speed HDMI cable (paid link) for optimal performance.
Step-by-step fix
If the quick checks didn’t resolve the issue, follow these steps:
- Update Firmware: Check if your receiver has the latest firmware. You can do this through the Onkyo website or the receiver's settings menu.
- Reset the Receiver: Perform a factory reset. This can usually be done by holding down the 'Reset' button on the receiver while powering it on.
- Check HDMI Settings: Go to the HDMI settings in the receiver menu and ensure that ARC (Audio Return Channel) is enabled if you are using it.
- Inspect Cables: Examine all HDMI and speaker cables for damage or loose connections. Replace any faulty cables.
- Reconfigure Inputs: Go through the input settings on the receiver and ensure each device is correctly configured.
- Test with Different Devices: Connect a different device to the receiver to see if the issue persists. This can help isolate whether the problem is with the receiver or the original device.
If it still doesn't work
If you’ve followed all the steps and the error code persists, it may be time to consult a professional technician or reach out to Onkyo support for further assistance.
Thinking About Upgrading Your AV Receiver?
If your receiver is causing recurring HDMI, eARC, or audio issues, it may be worth evaluating whether a newer model solves the problem at the hardware level. Our best AV receivers under $500 guide covers current picks with HDMI 2.1, eARC, and Dolby Atmos — including the Denon AVR-S770H and Yamaha RX-V4A which handle modern 4K/120Hz passthrough reliably.
FAQ
Q: What does the error code mean?
A: Error codes can indicate various issues, including HDMI connectivity problems or internal malfunctions. Refer to the user manual for specific codes.
Q: Can I use any HDMI cable with my Onkyo receiver?
A: While you can use any HDMI cable, using a certified high-speed HDMI cable is recommended for best performance.
Q: How do I reset my Onkyo receiver?
A: To reset, hold the 'Reset' button while turning on the receiver. Check the user manual for specific instructions for your model.
Q: Why is there no sound from my receiver?
A: No sound can be caused by incorrect input settings, faulty cables, or a muted receiver. Check these first.
Q: Is it safe to leave my receiver on all the time?
A: While it is generally safe, it’s best to turn it off when not in use to prolong its lifespan.