Look on the firewall directly above the accelerator pedal. You should see the L-shaped connector with a red tab. The red tab is what allows you to disconnect it. In my case, mine just pulled off.
If you pull on it and it won't come off, that would indicate the connection is ok. If it does, push it onto the post till it seats and won't come off without using the tab.
As an aside, I disconnect the battery here if I'm putting it in storage for more than a couple of months.