FC Block in LAD - can I detect when it is activated?

I have a Function Block (FC) that I call to activate a proportional valve on an analog output.

However, I want to add a lag before activating the output - if the FC call is not held for a certain amount of time, I don't want to do the action. Hence, I have tried using a TON in my that is activated when the FC is called. Please see attached screen capture.

However, I had to add a binary action before the TON (I had connected it directly to the left power first). Now my TON is never reset as if it has never lost power. Is there an easy way to detect when a FC is activated and deactivated?

Thanks.

Thanks again.