Dead battery, Keyfob cannot deactivate alarm

[alvinaus]

Hello
I was unable to remotely unlock the car ( 2004 XC 70) with the remote.
Got in with the key......no crank response on turning key ( interior lights/ dash warning lights turn on)
Thought it was the remote battery so I changed it.....still no response
I then noted that I had left the lights on so I assumed the battery was deadish
Connected a Type S Charger to the under hood terminals.....no difference

What do I do next?
Cannot open the tailgate. Disconnect the positive for a few minutes?

Thanks

[5underpressure]

Preferably the negative terminal, electrics get funky with low voltage, has enough to do something but not proper. There’s the higher current draw and heat associated with it often damaging.

[alvinaus]

Battery itself will be difficult (Impossible?) to access without opening the tailgate

[alvinaus]

Ok
All good
No need for any resetting
Got sidetracked by watching this video :


Turns out the engine hook is not grounded.