Tailgate window

Look above and to the right of the license plate for a rectangular, black release button. Push up with your right hand. You will hear a click if your battery is working. This releases the latch. Now lift window with right hand.

Is there a way to lock the trunk window on my 2000 jeep grand Cherokee

Absolutely. When you click the remote to lock the four doors and the rear lift gate, this also locks the rear window. It does that by electrically disabling that black release button from opening the rear window. Check it out.

Whenever I unlock the doors on my 2004 Grand Cherokee, the rear tailgate window pops open. Is there a fix?

Clicking the remote unlocks that rear window but it shouldn't pop open. Maybe there's tension on that latch that makes it open while unlocking. Look it over. Maybe it's binding or not fully closing/latching. Lubricate things and work it open and shut a few times.

Can you open the back tail gate if the power windows and locks don't work