Raspberry PI 4 wont boot with Expander PI fitted
1049 Views - Created 24/11/2020
Can you check that there are no solder bridges between the pins on the 40-pin GPIO connector? If you have a multimeter try checking the resistance between the 5V pin and ground and the 3.3V pin and ground. If the resistance is close to 0 ohms that would indicate a short circuit.
If you can not find any problems with the soldering on the GPIO connector there could be a problem with the Expander Pi itself in which case I will send you a replacement.
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