Rear door will not open

Try lubing the latch first and then opening and closing a few times to get it to operate smoothly

To replace the latch you have to take off the moulding first which is held in by push pins and or retainers so they come out. Same for the panel then you unhook the rods on latch and electrical connectors then remove latch. See pics

For your actuator pull the hvac fuse in dash with key on for 60 seconds sometimes they reset and work. For high speed check fuse and relay under hood fuse box it may be that or one of those. Also check same are for rear heat it should be marked on underside of box cover

And if your truck doesn't restart because you disconnect battery reset security system they won't reset like you did. Did you check relays and fuses underhood for blowers. Replace relay with a like one in fuse box if it runs you found the problem.

Make sure the key was on when you did that. Then see if it gets power if it does its the actuator if no power may be control head but will need scanning for that.

There are two relays for the rear doors- unlockand lock. You'll have to check and see if theyare working as well as your cargo door plates and see if the power is being sent there. If it is then it can be yur powerdoor actuator inside the door. There is also a fuse for it in the same fuse panel. It's on the left side under the dash. That's where the relays are.

See pic 2 4 and 6 are actuators there is actuator for lh side in 2nd pic. The one marked 4 in first pic is for rh side