If I recall correctly, the LED light does NOT come on if the receiver is not bound and the bind plug is not connected.

I went through the same thing a few times and I thought my receiver was bad.

Once, it merely failed to boot up. Turning it off and back on cured that.

Another my battery power was too low and it failed to boot. Oops a recharge fixed that.

Finally I found that it had lost the bind, and rebinding it solved the problem.