The Deep Dive Fix Files: Week Ending 30 May 2026
This is a weekly roundup of significant sports tech problems that the endurance community has encountered and, where possible, resolved. Each entry covers the issue, the affected hardware or software, and the current best fix or workaround known to the community.
Courses from Komoot and Strava Losing Turn Cues When They Sync to Garmin
Routes built in Komoot or Strava and transferred to a Garmin device are arriving with their turn-by-turn guidance degraded or absent. Garmin’s course processing pipeline applies its own schema to incoming route files, renaming, merging, reordering, or discarding course points in the process. Komoot’s own support documentation now describes this as expected behaviour for both its Courses Sync integration and manual GPX uploads, placing the fault at the point of import rather than in the originating application.
Affected devices include the Fenix 7, Fenix 8, Epix Gen 2, Forerunner 955, and Enduro 3. The result on the device is a route that displays the correct line on the map but delivers partial turn prompts or none at all. Garmin addressed a related course point fault in the Connect backend in late 2025, restoring clean handling for routes built natively in Garmin Connect. That fix does not extend to routes arriving from third-party sources, which remain subject to the import schema behaviour.
Two workarounds have produced reliable results. The first is to disconnect and reconnect the Komoot or Strava integration within Garmin Connect, then trigger a fresh sync. The reconnection regenerates the course file and frequently resolves the missing prompts. The second, for cases where the resync does not help, is to build the route in Plotaroute and export a Garmin FIT file directly into the device’s Garmin/NewFiles folder. This bypasses Garmin Connect’s course processing entirely and delivers the turn cues as authored.
Tacx ERG Mode Drifting Off Target Power Mid-Workout
Tacx smart trainer owners running structured workouts in Zwift, TrainerRoad, or the Tacx Training app are reporting ERG mode failing to hold target power. The target wattage is set correctly, but actual output sits well above or below it, with the trainer’s resistance failing to correct as cadence changes. In the most severe cases, resistance escalates toward the trainer’s maximum, rendering the planned workout unrideable. This pattern is widely referred to as the spiral of death.
Three distinct causes account for most reported cases. The first is the cadence window. Tacx ERG control operates reliably only within approximately 70 to 135 rpm. Below or above that range the trainer ceases to regulate effectively, and power tracks gear selection and cadence instead of the workout target. Holding cadence consistently within that band eliminates the problem for many owners and is the most effective first measure.
The second cause is PowerMatch conflict. Pairing a separate power meter, such as the Garmin Rally pedals or a crank-based unit, with PowerMatch enabled can create a feedback loop between the trainer and the meter, producing the maximum-resistance behaviour. Disabling PowerMatch entirely, or replacing it with a fixed power offset, resolves this in most cases.
The third cause is specific to the Tacx Neo 2T. Firmware 2.6.0 introduced a five-plus-second delay in power response and significant cadence over-reading. Garmin released firmware 2.7.0 through the Tacx Training app to address the cadence behaviour. Owners on the Neo 2T should confirm they are running 2.7.0 or later before investigating other causes. A separate but related fault, ERG control cutting out after approximately one hour and reconnecting in cycles, is linked to the Bluetooth connection rather than the ERG algorithm. Running the trainer control over ANT+ rather than Bluetooth resolves the dropout behaviour on setups where the head unit or training application supports it.
Garmin Watch Notifications Going Silent Without Warning
Phone notifications cease reaching the watch suddenly and without any apparent change in settings. The pattern affects owners across Forerunner, Fenix, and Venu configurations, and typically presents after a phone operating system update or a Bluetooth reconnection event. Several distinct causes are in play, and the correct fix depends on which applies.
On Android, the Garmin Connect 5.18 release in October 2025 changed the watch’s Do Not Disturb behaviour to mirror the phone’s DND state. Any period during which the phone was in DND silenced the watch entirely. Garmin reverted this in version 5.19, restoring independent watch DND. Owners should confirm Garmin Connect is on 5.19 or later. A number of owners found that installing 5.19 was not sufficient and that a force-quit of the application, a cache clear, and a device reboot were required before the revert took effect.
On iPhone, the most frequent cause is the Show Previews setting. Apple requires Show Previews to be set to Always or When Unlocked, found under Settings, Notifications, for any application to push alerts to a paired Bluetooth device. A setting of When Locked or Never silences the watch regardless of any Garmin-side configuration. Background App Refresh for Garmin Connect must also be enabled, and Low Power Mode will suppress notification relay when active.
For cases where the platform-specific steps have not resolved the issue, a clean re-pair resolves the majority of persistent failures. The watch should be removed from the phone’s Bluetooth device list entirely, both devices power-cycled, and pairing performed again from within Garmin Connect rather than from the phone’s Bluetooth settings menu. A factory reset of the watch alone, without first removing the Bluetooth pairing entry, does not resolve the problem in most cases.
Battery Suddenly Draining Fast After a Garmin Firmware Update
A sharp reduction in battery life immediately following a firmware update is among the most commonly reported Garmin complaints. The most recent wave has affected the Forerunner 255, 265, and 955 following firmware 27.09, but the pattern recurs across product lines with most major software updates. Three causes are responsible for nearly all instances, and they require different responses.
The first is the optical heart rate sensor remaining in active mode following the update. Normally the sensor cycles between active and low-power resting states depending on whether an activity is in progress. After a firmware update the sensor can fail to return to rest, sampling continuously and drawing current around the clock. The reset procedure is to start an activity, allow the watch to reach the initial activity screen displaying the GPS status bar, and then back out without recording. This cycle returns the sensor to its resting state, and battery life typically restores to normal within the subsequent charge cycle.
The second cause is the battery gauge losing its calibration. The gauge estimates remaining charge by comparing live voltage against stored minimum and maximum reference values, and a firmware update can clear those stored values. The result is a gauge reporting a substantially faster drain than is actually occurring. The recalibration procedure is to run the watch down to a low charge level and then charge it fully, leaving it connected for several minutes after reaching 100 percent. This re-establishes the voltage references and restores accurate reporting.
The third cause is a background process remaining active after the update. Garmin Connect or a Connect IQ application can remain continuously active for hours overnight, maintaining a persistent Bluetooth connection and loading both the phone and the watch. The phone’s battery usage statistics will confirm this: Garmin Connect or Connect IQ showing several hours of background activity during an inactive period is the diagnostic signal. Force-quitting the application resolves it in most cases. A recently installed Connect IQ application or third-party watch face is a frequent source of this behaviour, and removing it eliminates the drain.
Garmin Coach Plans Not Reaching the Watch
Garmin Coach training plans and their scheduled workouts appear correctly in the Garmin Connect calendar but fail to appear on the watch. Manually created workouts sync without issue. The fault is specific to Coach plans and has been reported across current Garmin Connect builds on both Android and iOS.
The least obvious cause, and the one most frequently resolving the issue on current app builds, is the calendar sync selection within Garmin Connect. Enabling only the Garmin coaching plans option in the calendar sync settings is not sufficient for the plan to reach the watch. Owners have found that also enabling events and challenges in the same list causes the coaching plan to sync correctly. That a single additional checkbox produces this result points to a fault in the sync logic rather than intended behaviour.
A second cause is the watch holding a stale calendar state, typically presenting as the message “Download your training calendar from Garmin Connect” without ever completing the download. A full application reinstall resolves this: log out of Garmin Connect, delete the application, unpair the watch from the phone’s Bluetooth settings, then reinstall and pair again through Garmin Connect. The plan appears under Run, Training once the sync completes.
For owners running both a watch and an Edge cycling computer, device priority is a third cause. Garmin Connect routes training plans to the designated primary training device first, and if that designation is set to the incorrect unit the plan will either fail to transfer or recalculate incorrectly for the wrong device type. The primary training device is set through the device list in Garmin Connect under Manage Device Priority. Correcting this setting and allowing several hours for the plan to re-sync resolves the routing fault.
A separate but related fault is Garmin Coach failing to register a completed workout. The activity records correctly in Garmin Connect, but the plan does not mark it as done and shifts the schedule as though the session was missed. Manually rescheduling the workout back to its original date and syncing restores the plan sequence.
AMOLED Burn-in and Image Retention on Garmin Watches
Reports of faint image retention on Garmin AMOLED panels have been documented across the Epix Gen 2, Venu series, Forerunner 265, Forerunner 965, and Fenix 8. The retention manifests as faint ghosting of static watch-face or data-field elements, typically only visible against a solid-colour test screen rather than in normal use, but representing a permanent change in panel behaviour once it appears. With the Forerunner line completing its transition to AMOLED following the Forerunner 70 and 170 launch, the question is directly relevant to a growing proportion of the user base.
The consistent differentiating factor in reported cases is always-on display. Owners who run AOD continuously, particularly with a high-contrast watch face holding static elements such as a battery bar, step count, or fixed digits in the same screen positions for extended periods, are the cohort reporting retention. Owners using gesture or tap-wake with the standard timeout report no issues after one to two years of daily use. The mechanism is established: organic pixels in AMOLED panels degrade at different rates depending on how long and how brightly they are driven, and static high-contrast elements at fixed positions accelerate that differential.
Prevention is effective when applied from the start of ownership. Leaving always-on display disabled removes the primary risk factor. For owners who want AOD, selecting a face built to Garmin’s AOD style guidelines, which use dimmed and outlined elements rather than solid bright fills and incorporate pixel-shifting techniques, substantially reduces pixel stress. Lowering display brightness and shortening the display timeout in normal use further reduce cumulative exposure. Third-party watch faces that hold bright static elements in fixed positions carry the highest retention risk.
Existing image retention cannot be reversed. It is a physical change in the organic light-emitting pixels and cannot be addressed through software updates, display recalibration, or any known user intervention. The practical implication is that the decisions made about always-on display and watch face choice from the first days of ownership determine the panel’s long-term condition.
Garmin Watches Failing to Charge Fully or Charge Cleanly
Two distinct charging faults are affecting current Garmin models, and the correct diagnosis determines the correct fix.
The first is firmware-related, present on the Fenix 8, Forerunner 265, and Forerunner 965 following the March 2026 firmware releases. The watch charges normally to 90 percent and then halts without error. The underlying cause is a coulomb counter calibration fault in which the firmware’s charge accounting diverges from the battery’s actual state and the charging circuit stops prematurely. This is a software fault, not a battery hardware issue. Garmin’s fix is firmware 21.20 for the Fenix 8 and firmware 14.18 for the Forerunner 265 and 965, both installable via Garmin Express. Owners who have not received the update over Wi-Fi should connect the watch to a computer running Garmin Express and apply the update directly.
The second fault affects every Garmin watch with rear-contact charging, from the Forerunner 245 series and Fenix 5 onwards, and is caused by contact corrosion. Sweat, body oil, and moisture trapped between the watch back and the wrist after workouts, swims, or showers accumulate on the charging pins as a thin film, progressing over time to visible green or white crust. The symptoms are intermittent charging: the cable connects only at a particular angle, the charge indicator illuminates and then drops, or the charging cycle starts and stops repeatedly.
The cleaning routine that restores reliable contact is to apply isopropyl alcohol at 90 percent concentration or stronger to a soft toothbrush and work it in small circles across the four pins on the watch back and the corresponding pins on the charging cable. Distilled water on a cotton swab serves as a milder alternative for light accumulation. Metal tools should not be used on the pins. The silicone dust caps sold as accessories for the charging port retain moisture against the pins and accelerate corrosion rather than preventing it. Rinsing and drying the back of the watch after workouts and swims before re-wearing or placing it on charge removes the primary source of accumulation before it can build.
Last Updated on 30 May 2026 by the5krunner

tfk is the founder and author of the5krunner, an independent endurance sports technology publication. With 20 years of hands-on testing of GPS watches and wearables, and competing in triathlons at an international age-group level, tfk provides in-depth expert analysis of fitness technology for serious athletes and endurance sport competitors. ID
