in the process of replacing my factory amp to a bluetooth aftermarket amp. want to use stock amp power source.

But have zero voltage with ignition on.

Any chance I have blown fuse? checked the box underhood but nothing relate to radio.

or some other switch needs to be on to get 12v?

Also, What's a good location to connect the switch blue wire?

edit: Turn out to be blown fuse for booster.

What's a good source for 12v switch wire?