Hi,
I am using :- SparkFun GPS-RTK2 Board - ZED-F9P (Qwiic) - SparkFun Electronics
I am observing that tiny backup battery is not working as I can’t lock GPS after quick power Cycle. If I want to replace this on baord is it any Coincell or it is rechargable battery coincell?
can anybody share link to battery used on this breakout board?
This one
I traveled the same path. Check out RTK-SMA - replace BBR (ML414H_IV01E) - source & tips?
@doug_f Thank you for the link. I am ordering my parts now.
Hi @ha11otronix ,
Please be aware that the battery on the SparkFun GPS-RTK2 Board - ZED-F9P (Qwiic) is different to the battery on the SparkFun GPS-RTK-SMA Breakout - ZED-F9P (Qwiic). The GPS-RTK2 battery is a Seiko MS621FE-FL11E. The RTK-SMA battery is Seiko ML414H-IV01E. Please make sure you order the correct one.
Also, are you sure the battery needs replacing? Have you checked the cell voltage after leaving it powered and charging for a few hours? Perhaps you have not saved the F9P configuration - to Battery-Backed RAM (and/or Flash)? You need to ensure the configuration is saved before disconnecting the power.
I hope this helps,
Paul
Thanks for the correction Paul! My bad. 
Sourcing & replacement tips from that thread can still help though, wouldn’t you agree? Your soldering & repair tips are SO good.
Hi Doug,
No worries! That thread is very useful. I just wanted @ha11otronix to be aware of the different battery types.
All the best,
Paul
Perhaps expand on this somewhat.
This is somewhat of a “cold start”, if the ZED is taking more than a minute to recover a GNSS fix, it’s indicative that the antenna is not working well, or poorly situated.
The battery is to maintain the RTC and BBR, so should hold time and location. I’m not sure it effectively holds the ephemeris.
For most of the other settings, pushing them into FLASH is typically how to ensure the receiver uses and retains them.
