i took my battery out of my 2015 F150 to boost lawn mower, when i went to put back in i placed the battery in backwards and hooked up positive to the negative and of course when i put the negative to the other post we got spark, very short as i pulled off and realized the issue. i then turned it around and reconnected properly. Now my service charge system came on and the wrench light as well as service 4x4. I then went to go to work Monday and the battery completely drained itself and the truck shut off. I put new battery in and got truck home. What you think i should try next, is it possible i may have fried the alternator or a computer issue? Or is there a relay i could have blown within the charging system. Thanks

 

Is the mega fuse blown that is connected to the battery? Does it try to start at all or what?

Put the battery on the charger and leave it for the night. It takes time for the battery charge light to go away.

 

Check all the fuses, I think you have 2 fuse boxes. If the problem persists, you have a dead alternator at minimum.