I installed a keyless entry remote start system, it starts the car and locks, but it doesn't unlock the doors and I'm not sure why cause I can hear the relay click, does the unlock need a positive output instead of negative like the lock does?

 

Lock and unlock are both negative trigger.

You should post the detail of the car such as year, model, etc. with each thread should other forum members can give specific help on circuits, wires, etc.

 

My car is a 1998 civic si (canadian) The unlock all wire seems to not work but the unlock drivers door wire works fine, so I think im happy with that