I am building a movement monitoring system on a Raspberry Pi 2. I've just put a meter on the 5V and GND pins, and I'm measuring ~10V. The 3V3 and GND show 7.5V.

What on earth is going on? Or have I got this wrong somehow?

BTW - Windows 10 IoT is running OK on the Pi.

  • 3
    If those voltages hit any of those pins, your Pi would likely release the magic smoke. If it hasn't, there's something amiss with your metering arrangement.
    – goobering
    Commented Feb 10, 2016 at 10:08
  • 2
    What are you using to measure the voltage with, a standard multimeter? It could one of many reasons that you are getting twice the expected reading. As a sanity check - maybe your meter badly needs calibrating (do you have a reference with which to check it?), or the input impedance of the meter is too low (see Why does an oscilloscope show a different voltage from a signal generator?), or you have the leads plugged in to the current measuring socket? Commented Feb 10, 2016 at 10:23
  • 2
    Your meter needs a new battery, or you have killed the Pi. What is the rating of your power supply?
    – joan
    Commented Feb 10, 2016 at 10:31
  • Ah - a 9V battery is reading as 11.7V. My meter seems chuffed. Commented Feb 10, 2016 at 13:49
  • The leads are in the correct sockets, and it's on the correct setting - but it seems far from correct. That will teach me just to trust it blindly. Thank you all. Commented Feb 10, 2016 at 13:50

1 Answer 1


A new battery in the multimeter has fixed the problem. I never knew a low battery would affect it's readings - I assumed if it switched on, it was good to go.

With the new battery it's reading 8.7V for a fresh 9V battery. Still not super-accurate (time for a new one I think), but at least it shows my Pi is OK.

Thanks for the help everyone. (I would mark someone's answer as correct, but they are all comments.)


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.