^Strange, because T5 should even release in pitch black and shoot at its slowest speed of 1/60. It focuses with an IR beam, also in pitch black.
I wonder if there might a spec or something on the circuit board, maybe a burnt or corroded contact.
Or the lens motor is wearing down, which would probably be the worst scenario.
The odd part is that it only happens after turning on, I can finish a whole roll trouble free after overcoming the initial hurdle.
I found this image of the bare top circuit what's under the button.
But I'm a bit hesitant to opening it up, I wonder if touching the wiring could still give a connection.
The shutter release should be the middle ring and the blocks on top and bottom should be the AF/AE lock.