Corrupt FIT Files

hi Steven,

had a look at the provided fit files

first important job you have to do is to clean folder 'tempfit/saf_hr' on your FR920XT

• while doing this also cleanup the ACTIVITY folder

only download hr data from the strap when watch and strap were separated or with swim

• when downloading hr data keep watch and strap in close proximity providing good data transfer
• downloaded hr data from one activity corrupted all other activities because of the stored file hrdata.fit on the watch !

check these files

• D6NF1956_with-repaired-downloaded-hrdata.zip
• D77F4445_with-repaired-downloaded-hrdata.zip

tip :perhaps not suited for th FR90XT ?

MostafaMossaad said:

Hi madmatt2314
I'm not sure I've understood your problems. But I "frequently" have issues downloading stored swim heart rate data (From Garmin HRM-Swim) to my Forerunner 965.

The workaround I've found to work almost always is.

1- Disable Bluetooth on your mobile phone (To avoid duplicated activities. More on that later).

2- When finishing your activity. Choose to save it. But *CANCEL* the heart rate data download. Save the workout WITHOUT the heart rate data.

(This will save an activity without heart rate data. And if your phone syncs that, you'll have an activity on Garmin Connect (And any other services connected to it) without the heart rate data.

3- Go to the activity details and THEN choose to download the heart rate data. The watch should search for your HRM, download the data, then treat/parse/add/etc.

(This will add/impose the heart rate data on your current activity. If you had synced before this step, Garmin Connect will create a new/duplicate activity, but with your heart rate data, and this new one "might" go to other services, or not. Depending on the Service. It won't go to Strava because Strava will believe it's a duplicate activity because it is of the same type and started at the same time as the previous one, but it will go as a duplicate to TrainingPeaks)

4- Now you can turn on Bluetooth on your mobile and then sync.

forgot to explain the 'why' corrupted

• question, any idea yourself why this happened, did you notice anything different during hr data download ?

the downloaded (corrupted) hr data from the strap gets appended to the original (not corrupted) fit file from the activity

• hence you get stuck with a corrupted fit file

Garmin's error handling for the hr data transfer is not working as it should since the introduction of the hrm-tri, hrm-swim

• the downloaded hr data has a checksum so it is easy to filter between good and bad 
• but this correction or request for resend data is not happening 

why the second swim got the same corrupted hr data appended as the first swim fit file

• the folder on the watch was not cleared by the watch after data processing
• again a cleanup Garmin software should do

best to contact Garmin Support and tell them about the mishap

• the more the better 
• but after all these years and still no change in this situation 

Thanks for all of your help.  I am not sure how it happened.  I can understand that second file being corrupted because I didn't clear the first one.  This has never happened in the past, so I'm at a loss.

Since the second swim with corrupted data, my watch battery only lasts about 4hrs now.  I have cleared the Activity folder and the tempfit/saf_hr but nothing changed.  Also I am having trouble with the bottom left button.  When i press it nothing happens.  It takes multiple presses to activate.  

I'm going to do a reset shortly, but I'm thinking I might need a new watch.