A few weeks back, we announced our decision to
recall our v1.1 balenaFins due to a USB issue at high temperatures, along with an in-depth
explanation of the issue.
We offer free repair for any customer that has purchased a v1.1 balenaFin, and many of our customers have already gone through the process. But since we're also tinkerers ourselves, there's no denying the thrill of being able to fix our own stuff. We created this guide to make that process as easy as possible.
Before we begin
Disclaimer
Attempting to perform the fix in any other way (including the steps detailed below) will result in a void of the balenaFin warranty. This process should only be performed by someone with highly developed soldering skills.
Hardware required:
- 2 x RES SMD 1K OHM 1% 1/16W 0402 ±100ppm/°C (i.e. RC0402FR-071KL).
- Soldering station or hand solder iron with fine solder tip*
- Tweezers
- Environmental chamber for heat testing. While this is not mandatory, it is the only way to verify that the balenaFin is working correctly at high temperatures.
Tutorial
First, make sure to remove everything connected to the balenaFin. This includes the power cable, complute module, coin-cell battery and any other peripherals.
Now it's time to desolder the original 47K resistors that were causing the issue. The picture below highlights the position of the resistors to be desoldered.
Once both resistors have been removed, solder the replacement (1KOhm) resistors in their place.
Testing
Finally, in order to verify that the process has been done correctly, we need to perform two tests: