Welcome to our forums! You seem to have a v1.0 balenaFin, can you confirm you’re following this process just to be sure:
Disconnect every cable from the balenaFin
Connect the micro USB cable
Connect the barrel jack
If the above doesn’t work, it’s usually one of three problems:
1- The compute module is not properly seated on the SoDIMM connector. This is sometimes difficult to spot, so make sure both clips are properly attached.
2- The micro USB cable is faulty. If you purchased a developer kit, try with the included cable. Otherwise, could you please try with a different cable?
3- Not using a CM3+ Lite. This is a less likely scenario, but please make sure you’re using a “Lite” version of the Compute Module 3. In the lite version, the chip highlighted below should be missing:
If you still have issues flashing the compute module, you can send us an email at store@balena.io to process a return. If you do so, please provide the order number for when you purchased it.