tailgate actuator

when locking or unlocking the d1 the actuator on the tail gate goes up and down then stays down. even when all other doors are open.
ive taken actuator off and its very limp! no resistance up or down. should there be? i'm thinking its too slack so it wont hold itself up?

any ideas appreciated!

If the door pin pops up but then drops back down slightly when unlocking is symptomatic of a broken lock spring.
All the actuator does is move the lock mechanism.

found the link....