ESP32-Cam No Response and Unable to Program - Timed out waiting for packet header
You're right. There is no LED when you power up your ESP32 cam. So this is normal.

Try to power it with the 5V, so you can power it from your USB instead of the 3.3V regulator of your FTDI. The ESP just need 50mA when in programming mode, so it should not be a problem for your FTDI.

Do you see anything on your serial output? Once you connect it in this way, you should set the baudrate to 115200 on your serial terminal and see some characters. 

Then, try to program it.
Once you see the output "...___...", press the reset button! Since you are just connecting RDX and TDX, you have to manually press "RESET" on your ESP32 module.

At this point the ESP will reset and enter in the programming mode.