How to change the Battery on an is250

Please advise on how to remove the wired connection on the left hand side of the plastic collar that covers the Battery? It seems by pressing it should slide off however no luck.

Sorry...had no idea this question was here. Only just saw this.

You are right, its a press and pull apart a bit like the headlight bulb connector

And, you should add that if you have a extra Battery around, you should connect it to the the leads before removing them frlm the old Battery. This way, the power is never lost, and the windows should stay programmed with tge clocks, memory seats and steering wheel. 

OBDII memory saver makes life easier when disconnecting batteries for replacement or other services. 

Can anyone clarify which bit of the IS250 Battery temperature sensor needs to be squeezed to allow it to be disconnected? I don't want to put too much pressure on it as the Battery casing looks fragile. The sensor is circled red on the attached image.