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.

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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.

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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.

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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.

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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.

Battery bugs like this are tracked in the watch battery life hub.

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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.

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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.

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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.

Quick answers

Why are my Komoot or Strava routes losing turn-by-turn cues when synced to Garmin?
Garmin applies its own course point schema when importing routes from third-party applications, which can rename, merge, reorder, or remove the turn cues created in Komoot or Strava. Komoot’s own support documentation describes this as expected behaviour at the point of import rather than a fixable bug. The issue affects the Fenix 7, Fenix 8, Epix Gen 2, Forerunner 955, and Enduro 3.

How do I get Komoot turn-by-turn navigation to work on my Garmin watch?
Disconnect and reconnect the Komoot integration within Garmin Connect, then trigger a fresh sync. This regenerates the course file and resolves missing turn prompts for most owners. If the resync does not help, build the route in Plotaroute and export it as a Garmin FIT file directly into the device’s Garmin/NewFiles folder, which bypasses Connect’s course processing entirely and delivers the turn cues as authored.

Does using a GPX file transfer fix missing Garmin navigation from Komoot?
GPX transfers go through the same Garmin Connect import schema that causes the problem and do not reliably resolve it. The most dependable workaround is the Plotaroute FIT file export directly into the NewFiles folder, which avoids Garmin Connect’s pipeline.

Has Garmin fixed the Komoot course point sync issue?
Garmin addressed a related course point fault in the Connect backend in late 2025 that affected natively built routes. That fix does not extend to routes arriving from third-party sources such as Komoot and Strava, which remain subject to the import schema behaviour. No further fix has been confirmed as of May 2026.

What is the Tacx ERG spiral of death and how do I stop it?
The spiral of death describes ERG mode progressively losing resistance control, with the trainer escalating toward its maximum output as the rider struggles to hold the target wattage. The most common cause is cadence dropping below approximately 70 rpm, at which point Tacx ERG regulation breaks down entirely. Holding cadence consistently between 70 and 135 rpm prevents it in the majority of cases.

What cadence range works reliably for Tacx ERG mode?
Tacx ERG mode controls resistance reliably between approximately 70 and 135 rpm. Outside this window the trainer stops regulating effectively and power tracks gear selection and cadence instead of the workout target. This applies across Tacx Neo, Flux, and Boost trainer families.

Why is PowerMatch causing my Tacx trainer to max out resistance?
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, driving resistance to maximum. Disabling PowerMatch entirely, or replacing it with a fixed power offset in the training application, resolves this in most cases.

How do I fix the Tacx Neo 2T power delay and cadence over-reading after firmware 2.6.0?
Garmin released firmware 2.7.0 for the Neo 2T to address the cadence over-reading and power delay introduced by 2.6.0. Install it through the Tacx Training app. Confirming you are on 2.7.0 or later should be the first step before investigating other causes of ERG instability on this trainer.

Why does my Tacx trainer keep disconnecting after about an hour?
ERG control cutting out after approximately one hour and reconnecting in cycles is typically linked to the Bluetooth connection rather than the ERG algorithm itself. Running the trainer control over ANT+ rather than Bluetooth resolves the dropout behaviour on setups where the head unit or training application supports ANT+.

Why have my Garmin watch notifications stopped working?
The most common causes are a Garmin Connect app update that changed notification behaviour, a phone OS update that reset notification permissions, or a disrupted Bluetooth pairing. On Android, Garmin Connect 5.18 silenced the watch whenever the phone was in Do Not Disturb mode; upgrading to 5.19 restored independent watch DND. On iPhone, the Show Previews setting under Settings, Notifications must be set to Always or When Unlocked for alerts to reach the watch.

How do I fix Garmin watch notifications not working on Android?
Confirm Garmin Connect is on version 5.19 or later, which reversed the DND mirroring change introduced in 5.18. If updating the app alone does not resolve it, force-quit Garmin Connect, clear its cache, and reboot the phone before reopening the app. For persistent cases, remove the watch from the phone’s Bluetooth device list, power-cycle both devices, and pair again from within Garmin Connect rather than from the phone’s Bluetooth settings.

Why are my Garmin watch notifications not working on iPhone?
Apple requires Show Previews to be set to Always or When Unlocked under iPhone Settings, Notifications for any application to push alerts to a paired Bluetooth device. A setting of When Locked or Never silences the watch entirely. Background App Refresh for Garmin Connect must also be enabled, and Low Power Mode will suppress notification relay when active.

Why is my Garmin watch not showing call or text notifications?
If platform-specific steps have not resolved the issue, a clean re-pair is the most reliable fix. Remove the watch from the phone’s Bluetooth device list entirely, power-cycle both devices, and pair again from within Garmin Connect. A factory reset of the watch alone, without first removing the Bluetooth pairing entry from the phone, does not fix the problem in most cases.

Why is my Garmin watch battery draining fast after a firmware update?
Three distinct causes account for most post-update battery drain. The optical heart rate sensor can get stuck in active mode and sample continuously around the clock; starting an activity and backing out from the initial GPS screen resets it. The battery gauge can lose its calibration reference values; a full discharge and recharge cycle restores accurate reporting. A Garmin Connect or Connect IQ application can also remain stuck running in the background overnight; the phone’s battery statistics will confirm this, and force-quitting the app resolves it.

Why is my Forerunner 255, 265, or 955 battery dying quickly after firmware 27.09?
The Forerunner 255, 265, and 955 are among the models most affected by battery drain following firmware 27.09. The most common cause is the optical heart rate sensor remaining in active mode after the update. Starting an activity, waiting on the initial activity screen until the GPS bar appears, and then backing out without recording resets the sensor to its resting state. Battery life typically returns to normal within the subsequent charge cycle.

How do I recalibrate my Garmin battery gauge after a firmware update?
Run the watch down to a low charge level, then charge it fully and leave it connected for several minutes after reaching 100 percent. This re-establishes the minimum and maximum voltage reference values that the gauge uses to estimate remaining charge, and restores accurate battery reporting.

Can a Connect IQ app cause Garmin battery drain?
Yes. A recently installed Connect IQ application or third-party watch face can remain continuously active after a firmware update, loading the Bluetooth connection and draining both the phone and the watch. Check the phone’s battery usage statistics: Garmin Connect or Connect IQ showing several hours of background activity during an inactive period is the diagnostic signal. Removing the recently added app or watch face eliminates the drain.

Why is my Garmin Coach plan not showing on my watch?
The most common cause on current app builds is the calendar sync selection in Garmin Connect. Enabling only the Garmin coaching plans option is not sufficient; you also need to enable events and challenges in the same calendar sync list for the plan to reach the watch. A second cause is the watch holding a stale calendar state, which requires a full Garmin Connect reinstall to clear. A third cause, for owners with both a watch and an Edge, is the primary training device being set to the wrong unit under Manage Device Priority.

How do I fix Garmin Coach not syncing to my watch?
Open Garmin Connect, go to calendar sync settings, and ensure both Garmin coaching plans and events and challenges are enabled. If the plan still does not appear, perform a full reinstall: log out of Garmin Connect, delete the application, unpair the watch from the phone’s Bluetooth settings, reinstall, and pair again. The plan should appear under Run, Training after the sync completes.

Why does my Garmin training plan show in the app but not on the watch?
This is a known sync fault specific to Coach plans and structured training schedules. Manually created workouts sync without issue; only plans generated by Garmin Coach or imported structured plans are affected. The calendar sync checkbox fix resolves it for most owners on current app builds.

Why is Garmin Coach not counting my completed workouts?
Garmin Coach sometimes fails to register a completed workout, recording the activity correctly but not marking the plan session as done and shifting the remaining schedule. Manually rescheduling the affected workout back to its original date in Garmin Connect and syncing restores the correct plan sequence.

Why does my Garmin watch show the message 'Download your training calendar from Garmin Connect'?
This message indicates the watch is holding a stale calendar state and is unable to retrieve the plan. A full Garmin Connect reinstall resolves it: log out, delete the app, unpair the watch from the phone’s Bluetooth settings, reinstall, and pair again through Garmin Connect. Do not attempt to fix it by factory resetting the watch alone, as this does not clear the calendar state.

Do Garmin AMOLED watches get screen burn-in?
Yes. Image retention has been documented on the Garmin Epix Gen 2, the Venu series, the Forerunner 265 and 965, and the Fenix 8. It manifests as faint ghosting of static watch-face elements, typically only visible against a solid-colour test screen. Once present, it is a permanent physical change in the panel and cannot be reversed through software or recalibration.

Does always-on display cause burn-in on Garmin watches?
Always-on display is the primary risk factor in reported cases. Owners who run AOD continuously, particularly with a high-contrast watch face holding static elements such as a battery bar or fixed digits in fixed positions, are the cohort reporting retention. Owners using gesture or tap-wake with the standard display timeout overwhelmingly report no issues after one to two years of daily use.

Which Garmin watches are at risk of AMOLED burn-in?
Any Garmin watch with an AMOLED display is subject to the same underlying physics. Confirmed reports span the Epix Gen 2, Venu 2, Venu 3, Forerunner 265, Forerunner 965, and Fenix 8. With the Forerunner 70 and 170 completing the transition of the Forerunner line to AMOLED, the risk applies to every current Forerunner model.

How do I prevent burn-in on my Garmin Fenix 8, Forerunner 265, or Forerunner 965?
Leave always-on display disabled, or if you use AOD, select a watch face built to Garmin’s AOD style guidelines that use dimmed and outlined elements rather than solid bright fills. Lower display brightness and shorten the display timeout. Avoid third-party watch faces that hold bright static elements in fixed positions for extended periods. These measures applied from the start of ownership are the only reliable prevention; existing retention cannot be undone.

Why is my Garmin watch not charging past 90 percent?
The Fenix 8, Forerunner 265, and Forerunner 965 developed a firmware fault following the March 2026 updates in which the charging circuit halts at 90 percent due to a coulomb counter calibration error. This is a software fault, not a hardware or battery failure. Garmin’s fix is firmware 21.20 for the Fenix 8 and firmware 14.18 for the Forerunner 265 and 965, installable via Garmin Express.

Is the Garmin 90 percent charging issue a hardware or firmware fault?
It is a firmware fault. The underlying cause is a coulomb counter calibration error in which the firmware’s charge accounting diverges from the battery’s actual state, causing the charging circuit to stop prematurely at 90 percent. The battery hardware is not failing. Updating to the correct firmware version via Garmin Express resolves it.

What firmware fixes the Garmin watch 90 percent charging bug?
Firmware 21.20 for the Fenix 8 and firmware 14.18 for the Forerunner 265 and 965. If the update has not arrived over Wi-Fi, connect the watch to a computer running Garmin Express and apply it directly. Do not replace the battery before confirming the firmware update has been applied, as the fault is software-side.

Why are my Garmin watch charging contacts not working properly?
Sweat, body oil, and moisture accumulate on the rear charging pins as a thin film that progresses to visible green or white crust over time, causing intermittent contact. Symptoms include the cable connecting only at a specific angle, the charge indicator flashing and dropping, or charging starting and stopping in cycles. This affects every Garmin model with rear-pin charging from the Forerunner 245 series and Fenix 5 onwards.

How do I clean Garmin watch charging contacts?
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 is a milder alternative for light accumulation. Do not use metal tools on the pins. The silicone dust caps sold for the charging port trap moisture against the pins and accelerate corrosion; remove them. Rinsing and drying the back of the watch after workouts and swims before re-wearing or charging prevents accumulation before it begins.

Browse every issue in the archive at the Deep Dive Fix Files hub.

Last Updated on 28 June 2026 by the5krunner