by linuxelf » Thu Jan 17, 2013 10:22 pm
I was just playing around with my spiffy new Pi T-Cobbler board, and noticed that the voltage drop between either of the two 3v3 pins and ground was reading only 1.6v. the 5v pins both read 5v, but the 3v3 pins only read 1.6v. I pulled the ribbon cable off, and tested voltages on the raspberry pi directly, and sure enough, there was 3.3v on both of those pins. I did a connectivity test on the various pins on the cobbler, and found that the two 3v3 pins were connected to each other, (This appears to be by design, as there are traces on the PCB connecting those pins) and I noticed that there was connectivity between all 5 ground pins (also apparently by design) but no other pins were connected to each other, and all other pins had good connectivity from the ribbon cable connection through to the breadboard connection. Can anyone help me track down what would cause the voltages to be low?