This discussion has been locked.
You can no longer post new replies to this discussion. If you have a question you can start a new discussion

Speed Sensor 2 with good battery repeatedly disconnecting and reconnecting from multiple GPS devices

Back early in December, in the middle of a ride, my speed sensor started disconnecting and reconnecting repeatedly on me.  I've attached a zoomed-in picture of the latter part of that ride -- looks like the drops started about ten minutes from end.

A graph of minutes 38-42 of a ride.  The speed line is continuous and even up til around 35:15, then after that contains very conspicuous gaps, that don't coincide with stops or slowdowns -- just signal drops.

My first thought was a dying battery, so I replaced it. But the speed sensor was still disconnecting/reconnecting after installing a fresh battery, so that wasn't it.  (And the activities on Garmin Connect show "Battery Status: OK" for all of them, atop that.)

My next thought was a bad firmware update (despite the bad behavior starting mid-ride), because I had vague recollection of the Edge 830 firmware updating somewhat recently.  But when I finally got around to checking, the preceding rides, that ride, and following rides all were using the same firmware on my Edge 830 (9.10) and on the Speed Sensor 2 (2.3).  So that doesn't make any sense, either.  I also tried updating the Edge 830 firmware, to the 9.22 beta.  Still dropping and reconnecting.

Then I figured I'd switch to recording on a Forerunner 945 instead, at that point still assuming that the problem was on the Edge 830.  But on switching -- with the 945 connecting to the Speed Sensor 2 -- I discovered I was still getting disconnects/reconnects.  So clearly the problem is with the speed sensor.

Based on searches here, particularly this question -- I next tried to fuss with the metal spring contacts, to force them into the CR2032 battery harder.  That worked for the immediate next ride -- no continuity gaps in the recorded speeds.  But then the ride after that ride, things returned to their dropping/reconnecting ways.

I got the speed sensor with the Edge 830 back in May 2019, so it's out of the original one-year warranty.  If it's not the metal springs (or at least forcing them into the battery harder doesn't work), and it's not the battery at fault, is there something else I should try?  Or has my speed sensor just given up the ghost and I should get a new one?

  • I have the same issue.

    I am using a Garmin 530, the speed sensor is updated to 2.3 and it has battery. 

    It is disconnecting and recording less distance.

  • Did the new battery you fitted have a bittering agent applied to it that is supposed to stop children swallowing them?

    I have seen various reports that this coating can cause problems with low current devices such as Garmin sensors. Try a battery without a coating and give the battery contacts in the sensor a clean before inserting the battery.

    I try to buy batteries without this coating but it is becoming harder.

  • I have read in the documentation about the likelihood of a magnetic issue in rear hub or the chain. I will try to put the sensor on the front wheel. This issue is happening for last two days,  and it coincide with the change of the wheel and the chain.

  • Verified. I have set the sensor on the front wheel and changed the battery and it has worked.

  • I was having this issue and reached out to Garmin support. They sent me a new one and it was fixed.

    The front wheel isn't an option for all as the hub is much thinner on more bikes and doesn't allow the sensor to hook in.

  • I've had this same issue with two different speed sensors on two different bikes. I was hoping the latest FW update would help, but it's still happening. Pretty annoying. Frowning2

  • Do you also have the Speed Sensor 2 paired with Garmin Connect Mobile as well as your Garmin device?

    I had a brief period of regular dropouts of the Seed Sensor 2 on my Edge 1030 Plus and fenix 6X after adding the sensor to Garmin Connect Mobile for Android to try and update the firmware. Once I realized the dropouts had started when I added the sensor to Garmin Connect Mobile I removed the paring with Garmin Connect Mobile (and phone's Bluetooth settings) and the dropouts stopped.

  • I'll have to check. I honestly didn't even know you could add it to Connect Mobile, but maybe I did at some point.

  • For what it happens to be worth, I eventually just bailed on the sensor, bought a new one, and haven't had issues with the new one.  I'm inclined to think the electronics just flaked -- warranty period is a reasonable indicator as to when, actuarially, sensors can flake, and I was past it at that point.

  • Just checked and nope, not connected to Connect Mobile app or phone's BT. :| Based on the many threads on this forum related to this issue and the fact I have the issue with both of my sensors makes me think it's not a speed sensor problem per se, but likely related to my phone's BT connection to the Edge causing issues. Next MTB ride I'm going to turn off my phone while I ride and see if that solves it.