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Hi all .... newbie here! I'm trying to fix a friend's smoothie blender which is totally non-operational. I have thoroughly checked all the mains voltage side of things and found no fault. On the PCB I have replaced the Triac to no avail and checked the single disposable fuse which has good continuity. I have tested the motor and the LED switches separately and both are good. My problem seems to be that there is no 5V current to the LED "switches" which appear to be not switches at all as they are all solid state and there's nothing to depress! Can anyone explain how these "switches" work please and which components/s are most likely to be the culprits? Thanks in anticipation Rod

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Hi Rod, welcome! Sounds like you've already done some solid troubleshooting. Those LED “switches” you’re seeing are likely capacitive touch sensors — they detect changes in capacitance when your finger is near, rather than relying on physical movement like a traditional switch. For these to work, they need a stable 5V supply, so the fact you're not seeing 5V suggests a power rail issue.

I'd recommend checking for a voltage regulator (like a 7805 or a small buck converter chip) on the PCB that steps down mains or intermediate DC to 5V. Also check any nearby electrolytic capacitors or diodes — a failed one there could prevent the 5V rail from coming up. If the regulator itself is dead or not getting input voltage, that could explain why the switches aren't working.

If you can post a clear photo of the board, especially near the area where the 5V line originates, someone might be able to help pinpoint the issue further. Good luck with the repair!

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Hi Darren I have had no luck so far ! As you suggested I have taken some photos which I am hoping might help. I have changed out the 3 capacitors at E1, E4 and E5 on the PCB to no avail. There is a mysterious small PCB which sits just below a disk directly under the motor fan. It has a 5V terminal so it must be something to do with it somehow. I have removed and cleaned it but cannot understand what it does. I think I might be boxing above my weight but I don't want to give up! Here are the links to the photos - hopefully you will be able to see them. Thanks - Rod https://ibb.co/N6XM4dL2 https://ibb.co/JRJMQxrp https://ibb.co/rfmKK7N0 https://ibb.co/Kxntdpnb https://ibb.co/FkWH96Tj https://ibb.co/cKY6TT7H

Thanks so much Darren I really appreciate your comprehensive answer....it has given me some understanding and also some ideas. I'm in the process of changing out three of the capacitors, if that doesn't work I'll come back with a photo. Thanks again. Rod.