Bose QuietComfort Headphones F33 Fix (Error Code Guide)

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What This Error Means

F33 on Bose QuietComfort headphones = firmware / startup fault.

The internal software fails its boot check or update, so the headset either won’t turn on properly, won’t connect, or gets stuck in an endless update loop.

Official Fix

Run these in order. Don’t skip steps.

  • 1. Give it a proper charge.
    • Use a basic 5 V phone charger, not a high-watt laptop USB-C brick.
    • Use a known-good USB cable (preferably short, not beat-up).
    • Leave it charging at least 30 minutes, even if the LED looks odd or blinks.
    • If there’s still no life after 30–45 minutes, move on to reset.
  • 2. Do the standard Bose reset.
    • Power the headphones off.
    • Wait 30 seconds.
    • Connect them to a wall charger with the USB cable for about 5 seconds.
    • Unplug the cable.
    • Wait 1 full minute, then try powering on again.
    • This is the reset sequence Bose documents for most QuietComfort models.
  • 3. Do a deeper reset / Bluetooth wipe.
    • On a lot of QC models, holding the Power/Bluetooth button and Volume – (minus) together for ~10 seconds forces a deeper reset and clears the paired list.
    • If your buttons don’t match that description, look up your exact model on Bose’s support site and follow their “restore factory settings” steps.
    • After the reset, re-pair the headphones with your phone and check if F33 still shows in the Bose app.
  • 4. Reinstall firmware using the Bose app.
    • Open the Bose Music or Bose Connect app (whichever your model uses).
    • In your phone’s Bluetooth settings, forget/remove the headphones.
    • Force-close the Bose app, then reboot your phone.
    • Open the Bose app again and pair the headphones through the app, not just via Bluetooth settings.
    • If the app offers a firmware update, run it while the headphones stay plugged into power and close to the phone. Don’t walk away with them.
    • If the update completes and the app no longer shows F33, you’re done.
  • 5. If F33 won’t clear, Bose wants it back.
    • At this point, Bose’s official line is: contact support for warranty service or a paid exchange.
    • Persistent F33 usually means a bad firmware chip, main board fault, or a battery that’s unstable enough to crash updates.

The Technician’s Trick

When the official routine doesn’t kill F33, here’s what techs actually try before writing it off.

  • 1. Force a wired firmware reload from a computer.
    • On a laptop or desktop, open a browser and go to Bose’s firmware updater (search for “Bose BTU updater” and open the official Bose page; type the address manually).
    • Use a short, good USB cable to connect the headphones directly to the computer.
    • Make sure the Bose phone app is closed so it’s not fighting for control.
    • Let the updater detect the headset. If it offers to reinstall or update firmware, do it and don’t touch anything until it hits 100%.
    • If it hangs, move the cable to a different USB port and try again.
  • 2. Clean and reseat the charging port.
    • Unplug everything from the headphones.
    • Blow out the USB-C or micro-USB port with dry compressed air. No liquids, no metal picks.
    • If you have electronics-safe contact cleaner, a tiny burst into the port, then let it dry for several minutes.
    • Try a different USB cable and a basic 5 V / 1–2 A wall charger or computer USB port.
    • Glitchy contacts can break the data lines the firmware update needs and cause F33.
  • 3. Long power hold to drain ghost charge.
    • Disconnect the charger and any audio cable.
    • Press and hold the Power/Bluetooth button for a full 30–40 seconds, even if no lights change.
    • Let the headphones sit for 5 minutes.
    • Put them back on charge for at least 30 minutes, then try powering up again.

If F33 survives all of that, you’re probably looking at a bad main board or internal battery module, not just a software tantrum.

Is It Worth Fixing? (The Financial Verdict)

  • ✅ Fix: F33 clears after reset/firmware reload, or Bose offers a flat-rate repair that’s clearly under half the price of new QuietComforts.
  • ⚠️ Debatable: Out of warranty, F33 keeps coming back, or a shop quotes a board/battery job at roughly 50–60% of a new pair.
  • ❌ Replace: Headphones are several years old, F33 is permanent even after a wired firmware reinstall, and any repair quote is near new-QC money.

Parts You Might Need

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See also

Dealing with F-series codes on other gear too? These walk-throughs might help: