Causes
- Dirty or corroded charging contacts on the back of the sensor — The WHOOP 5.0 charges through gold-plated pogo-pin contacts on the underside of the sensor pod. Worn 24/7, the pod accumulates sweat, skin oils, lotion, and dust that bake onto the contacts. When the residue layer builds up, the electrical connection to the PowerPack or wired charger becomes intermittent or fails entirely — the charger shows its LED but the app still reports the device as dead or offline. Community threads on charging failures frequently resolve after cleaning the contacts with alcohol.
- The Wireless PowerPack itself is depleted or not actually charged — The Wireless PowerPack is a separate battery that stores roughly 4–5 full sensor charges. Its LED shows the PowerPack's own charge state, not the sensor's. If you attach a drained PowerPack to the sensor, nothing charges — and because the LED behavior is easy to misread, users often believe the sensor is broken when the pack simply needs to be charged first via its USB-C port. One owner's "Not Charging, But Battery Pack is Charged" thread describes exactly this confusion after the sensor fully died.
- Poor alignment or incomplete seating of the PowerPack on the sensor — The Wireless PowerPack slides over the sensor pod and must seat fully so its charging contacts mate with the sensor's pogo pins. If the pack is clipped on at an angle, shifted to one side, or blocked by a thick band or case, the contacts never touch and no charge flows. The PowerPack can also be knocked out of alignment during sleep or workouts, stopping charging mid-cycle without any visible error.
- Battery in deep-discharge protection mode after being left dead — If the WHOOP 5.0 sits uncharged for weeks, its battery management system disconnects the cell to prevent damage. In this state the sensor shows no LEDs, gives no response to taps, and the app reports it offline even while it sits on a fully charged PowerPack. The protection circuit needs sustained charging voltage for a while before it reconnects the cell — users who give up after a few minutes mistake this recovery phase for a dead device.
- Firmware bug hiding the charging indicator or blocking charge detection — After certain firmware updates, owners reported the battery pack's state-of-charge percentage disappearing from the app's charging screen, and in some cases the sensor not registering that a charger was attached at all. In the "5.0 Battery Pack Charge Level Missing" thread, the indicator only returned after toggling Bluetooth and reseating the pack several times — evidence that the charging-state display and detection logic on the 5.0 can glitch after updates and make a working charger appear broken.
How to Fix
- Clean the charging contacts on the sensor and both chargers — Remove the sensor from the band. Use a lint-free microfiber cloth slightly dampened with 90%+ isopropyl alcohol to wipe the gold pogo-pin contacts on the underside of the sensor pod, the contacts inside the Wireless PowerPack, and the pins on the wired charger. Gently work the cloth into the recessed area around the pins where sweat and oils collect. Allow 5 minutes for the alcohol to fully evaporate before charging. This single step resolves the majority of "won't charge" cases caused by residue buildup.
- Charge the PowerPack first and confirm its own LED — Plug the Wireless PowerPack into a USB-A or USB-C wall adapter using the cable that shipped with it and charge the pack fully until its LED shows solid (typically green or white, depending on revision). A depleted pack cannot charge the sensor. Then attach the fully charged pack to the sensor and confirm in the WHOOP app that the charging screen appears — you should see the battery icon animate with the sensor's charge level. If the app shows the pack's percentage but the sensor level is not rising, proceed to the next steps.
- Re-seat the PowerPack with proper alignment — Slide the Wireless PowerPack fully onto the sensor pod until it clicks into place, with the pack's charging contacts firmly against the sensor's pins. Ensure no band material, case, or debris is between the pack and the sensor. If the sensor is inside a band, remove it from the band and charge it bare to rule out the band blocking contact. Press the pack firmly for a few seconds and watch for the app's charging indicator or the sensor's LED to confirm contact.
- Try the wired Basic Charger as an alternative — The WHOOP 5.0 ships with a wired Basic Charger that connects to the sensor's pogo pins via a cradle. If the Wireless PowerPack will not charge the sensor, attach the wired charger to the sensor and plug it into a wall adapter. If the wired charger works but the PowerPack does not, the pack's charging circuitry or contacts are faulty and should be replaced by WHOOP. If neither charger works, the sensor's own charging circuit may be at fault — continue to the recovery steps below before contacting support.
- Perform a deep-charge recovery for a dead sensor — If the 5.0 is completely unresponsive (no LEDs, app shows it offline), it may be in deep-discharge protection. Attach the sensor to a fully charged PowerPack (or the wired charger) and leave it untouched for 2–4 hours — do not tap it, move it, or check it repeatedly. The protection circuit needs sustained voltage to re-evaluate and reconnect the cell. After the recovery period, double-tap the sensor; the LED should flash to show the charge level. If it lights up, charge to full before wearing it again.
- Reset the charging detection by reseating the pack and toggling Bluetooth — For charging-state glitches after a firmware update (missing charge indicator, sensor not detecting the charger), power-cycle the pack: slide it off the sensor, toggle Bluetooth OFF and ON on your phone, then slide the pack back on. Repeat the slide-off/slide-on cycle a few times while watching the app. In the community thread where the pack's charge percentage vanished after an update, exactly this sequence restored the indicator. If the sensor still does not register the charger, reboot the sensor from the app (More → Device Settings → Reboot Device) if it has any charge, or after the deep-charge recovery in step 5.
- Contact WHOOP Support for a replacement charger or sensor — If the sensor charges with the wired charger but never with the PowerPack, or if it will not charge with either after cleaning, contact [email protected] or open a ticket via the app (Profile → Help & Support → Contact Support). WHOOP will typically send a replacement Wireless PowerPack or sensor under the device warranty included with your membership. If you are still inside the 1-month trial and the device is faulty, you can return it through More → My Account → Membership → Cancel without a restocking fee as long as you ship both the sensor and the wired Basic Charger back within 7 days of the return label being issued.