If the light is flashing but it isn't turning over with the key then you have two problems. One is the key isn't recognized which the relearn procedure or a scan tool can correct. The other is that there is still an issue with the ignition switch power, which is likely also why the relearn isn't working, it sounds like the body control module isn't getting the signal from the switch telling it to start.
You say you can get it to crank under the hood, Are you doing that by jumping the relay? If so and you leave the key on, does it run a couple seconds and shut off? If it only cranks without trying to start the problem is more likely the run circuit from the switch not sending power. That circuit also tells the fuel pump to turn on and prime. To see if it may be the issue you can go to the run relay in the same box under the hood. See if you can jumper it and try to start it. Also check the IBN Trans D fuse (10am) in the same box for power.
I attached the switch wiring functions below.
Pin 1- Battery voltage in accessory and run positions
Pin 2- Battery voltage constant
Pin 3- Battery voltage in run or start positions
Pin 4- Battery voltage with only key in, 5 volts with key in run position. Less than 5 volts volts in the start position. This is the signal for the key reader having the correct key.
Pin 5- Bias voltage from BCM - 5 volts
To test these you leave the connector in place but use a pin to probe the connections in place for the correct voltages.
In the above video that testing is in the first 6 minutes. If you have the correct voltages in each position then the issue is not in the switch now and is in the relays or wiring.
Images (Click to enlarge)
Saturday, August 22nd, 2020 AT 11:45 AM