Yamaha PASC5 X0S-00 E-bike charger 42V only providing 12 V

[MrBojangles]

Hey Guys!

Hoping I can get some help here. I have a e-bike charger with 4 pins on the output. It has a light but the light does not turn on.

When I check the voltage on the 4 pins on one of the pairs I get 12 V. On the other pairs the voltage keeps changing.

Nothing looks damaged and there are no shorts on any of the capacitors. I've ordered a ESR meter to measure the capacitance of the capacitors but it will take a while for the package to arrive.


Any tips?

Thanks

[Sam Scarbo]

You may check the device TJ30S6M3. It is near the two big capacitors near the output. It could be acting as a fast switching high-current rectifier.

[MrBojangles]

You may check the device TJ30S6M3. It is near the two big capacitors near the output. It could be acting as a fast switching high-current rectifier.

Thanks for the tip dude. You were close. It was the two output capacitors. I removed them to check the capacitance but my multimeter wasn't able to measure so I soldered them back and then it worked. So it must have been the solder joints.

Anyway looks like it's a good tip in general to check the output capacitors when the output voltage is low.