Last week while cutting some walnut with my Ryobi track saw, it kept stalling on me. Turns out the battery was nearly dead because the charger stopped working and the status LEDs weren’t lighting up at all when plugged in.

I opened up the charger and didn’t see burn marks or swollen capacitors anywhere.

Then I found a video on YouTube and sure enough, the resistor at R71 was wide open, reading 152 kΩ on the multimeter.

It’s a surface mount resistor labeled R500, which means 0.5 Ω. I don’t have any resistors that size, so I soldered in a couple of 1 Ω resistors in parallel.

It’s not pretty, but it properly read 0.5 Ω on the multimeter.

I put it back together, plugged it in, and the red LED lit up. Took it down to the shop, put a battery in, and the charger is back in the rotation!