Bose QuietComfort Headphones F35 Fix (Error Code Guide)

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What This Error Means

F35 on Bose QuietComfort headphones basically means a firmware / power fault.

The headphones start to boot, hit a software glitch or bad power reading, and then either won’t connect over Bluetooth or won’t power up cleanly.

  • Typical signs: random shut-offs, stuck white/amber LED, Bose app showing F35 and refusing to connect, or Bluetooth audio cutting out while wired audio still works.

Official Fix

Do the factory-approved steps first. Go in this order and test after each one.

  • 1. Basic power and cable check
    • Plug the headphones into a known-good USB cable and a wall charger (not a laptop or car port) for at least 30 minutes.
    • Wiggle the USB plug gently at the headphone side. If the light flickers or charge cuts in and out, you may have a bad cable or loose port.
    • Look in the USB port on the headphones. Blow out dust; stop if you see bent or broken pins – that needs pro repair.
  • 2. Soft reset the headphones
    • Power the headphones off.
    • Wait 30 seconds.
    • Connect them to the charger with the USB cable for about 5 seconds, then unplug.
    • Wait another 1 minute, then power them back on and see if F35 is gone.
  • 3. Clear the Bluetooth list and re-pair
    • Turn the headphones on.
    • Slide and hold the power/Bluetooth switch toward the Bluetooth icon for about 10 seconds.
    • You should hear the pairing prompt and see the LED flash blue.
    • On your phone / laptop, go into Bluetooth settings, Forget the Bose headphones, then pair them again from scratch.
  • 4. Update the firmware
    • Install or open the Bose Connect or Bose Music app on your phone.
    • Connect the headphones in the app if they will connect at all.
    • If the app offers a firmware update, run it and let it finish. Don’t unplug or let the battery die mid-update.
    • If Bluetooth won’t connect, use a computer with a USB cable and Bose’s firmware updater site instead.
  • 5. Factory reset (model-specific)
    • Bose uses different button combos for different QuietComfort versions.
    • Go to Bose’s official support page for your exact model and follow the factory reset procedure once, start to finish.
    • Don’t spam the reset combo over and over – one clean reset is all you want.
  • 6. When the manual says “stop”
    • If you’ve done power check, soft reset, Bluetooth clear, firmware update, and a proper factory reset and F35 is still there, Bose’s line is simple: contact support.
    • If you’re in warranty, do that now. Opening the headphones or swapping parts yourself will usually void the coverage.

The Technician’s Trick

Out of warranty and still stuck on F35? This is the hard reset that actually scares the fault out sometimes. Not in the manual, but it’s what bench techs do.

  • 1. Hard power-cycle the battery
    • Power the headphones off.
    • On most QuietComfort models, the right earcup holds the board and battery. Gently pull off the right ear cushion with your fingers – it’s clipped, not glued.
    • Remove the small screws around the plastic cover. Keep them in a cup so you don’t lose them.
    • Lift the cover carefully; don’t rip the speaker wires.
    • Find the small battery connector going from the battery pack into the circuit board.
    • Unplug that connector straight out. Don’t lever it sideways and don’t pull on the wires.
    • Leave it disconnected for at least 60 seconds to let the board fully discharge.
    • Plug the connector back in firmly, making sure it’s fully seated.
    • Reassemble the cup, refit the cushion, then give the headphones a full charge.
    • Power on and test Bluetooth again. Many “stuck” F35 faults die right here.
  • 2. Wired-only fallback if Bluetooth stays cursed
    • If F35 keeps coming back but they at least power on, plug in a 2.5mm to 3.5mm audio cable to your device.
    • They still need some battery for noise cancelling, but wired mode is often more stable when the radio firmware is acting up.
    • Use them this way while you decide if a board-level repair is worth the cash.

Note: layouts and screw counts vary by revision. Take photos as you go so you can put everything back exactly how it was.

Is It Worth Fixing? (The Financial Verdict)

  • ✅ Fix: Headphones under ~4 years old, shell and cushions in good shape, and F35 clears with a reset or a simple battery swap (parts usually under $40).
  • ⚠️ Debatable: F35 plus weak battery and worn pads; a shop quote in the $70–$120 range is borderline unless you really like this exact QuietComfort feel.
  • ❌ Replace: Cracked headband, water damage, or F35 coming back even after a new battery; main-board work often lands close to the price of a new set.

Parts You Might Need

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See also

Dealing with other devices spitting out F-series codes? These guides break those down too: