Hood ajar warning acting funny

I have searched but found nothing on my problem .
I never noticed this before by doing this in the past -, with the truck off , I opened the hood and hooked up a battery charger . Even after leaving the truck for several minutes , the hood ajar warning is on, on the dash and will not go off unless I shut the hood . I cannot close the hood without removing my charger .
I do not think this has ever happened before when putting the charger on and leaving the hood open . I have left the charger on for over a week at a time and would have seen the warning if it was on the whole time .
The only thing I changed was putting an adapter between the rear view mirror to allow the plugging in of my dash cam . i removed the adapter and it still has the same problem
Anyone know what is going on ? Would anyone try this on their truck to see if it is the same ?

 

Are you using a trickle charger or a full battery charger? If it's full charge, the battery should be disconnected to charge.

 

It is a fully automatic charger from Noco G15000 that can be left on indefinitely . Also , even without the charger , If I leave the hood open the warning stays on and will not go off until the hood is closed .

 

Nice charger. I dunno, maybe disconnect both terminals for a few minutes, then reconnect and see if the light goes out. You may lose your radio settings.

 

I always look for the easiest fix first. Perhaps the adapter install and removal had something to do with it. A computer reset may fix it.