No power no sound no boot after battery replacement

Thanks for you're reply lemerise. Which cable is this exactly? I have triple checked all connections on the logic board. And have had no further success.

On further inspection I noticed when I hold the power button I hear a very faint clicking noise coming from the fan area of the logic board. I don't know what that means.

OK so the logic board seems to receive power. Did you try a SMC reset ?

I've tried an smc reset a couple times although this does nothing. I have no warranty for this computer so bringing it to apple repair is a last resort

Also if i plug the magsafe in the light stays a consisten green

Find the two power pads on the logic board (most of the time they are located near the top case connector) and with a multimeter settled to DCV/20 put the black probe on any logic board screw for ground and the red prob on one of the two power pads. Try this with the battery disconnected from the logic board. With the AC adapter connected the reading should be 3.42 volts (G3hot power line) on one pad and 0 volt on the other. If you don't get that reading the logic board wont power on. If you don't have this reading, disconnect the AC adapter, disconnect the top case ribbon cable, connect the AC adapter and double check the power pads voltage. If you still don't get the 3.42 volts you should remove the logic board and check the magsafe dc in board voltage and the main power fuse near the magsafe board connector.