m1muzik - 24 November 2018 11:36 AM

Hello everyone.

Welcome to the forum.

m1muzik -

I too am having the same power on issue with my s90 and suspect the similar components are faulty. I wanted to know what places is best to order the voltage regulators and which type is recommended.

The voltage regulators don’t tend to fail.

m1muzik -

So far I have ordered parts (electrolytic capacitors and currently looking for SMD chip-type capacitors) from eBay and Amazon. I had tried to order the parts via Yamaha’s support site but I haven’t had any luck especially using the correct part number references from the service manual. Any info would help.

Thanks

The electrolytic caps previously mentioned are typically what needs to be replaced. It’s not necessary to order such parts from Yamaha.

Your member profile doesn’t indicate your location, so making recommendations for parts suppliers is difficult. In the US, Mouser Electronics and DigiKey Electronics are usually good choices.

5pinDIN -

Thanks for the fast reply! Yes, I am located in the United States. I’ll check those two places to order the rest of the capacitors that I need to replace. I have noticed on PSU board that there are darker lines coming from one of the regulators, I figured the regulator in that section would be burnt or needs changing. I’ll continue to replace the capacitors in my case and see it that resolves my power on errors.

Thanks again!

-M1muzik

You’re welcome.

Have you checked voltages to determine if the regulator is/isn’t functioning correctly? Sometimes bad caps can cause excessive dissipation in such a device, or heat sinking is insufficient due to a mounting issue.

Typically Yamaha doesn’t manufacture the power supply, it’s purchased from another supplier. Therefore there’s usually no schematic or parts information for it in the SM. Yamaha provides a part number for the entire PSU.

If you need to replace the regulator, what identification do you see on the part?

Hello,

Sorry for the late reply, I had forgotten my password and tried several times to reset my password and finally I was able to login back. Thank God I had found my password written somewhere in my phone, the password reset on this forum doesn’t work. Here is a picture of the PSU board. The middle section looks alittle dark especially around the voltage regulator area.

Picture 1

Main Picture