2006 Impala - My back seat won't open, after looking over everything and playing around I was able to get the sides to open but can not get the middle to open to allow the seat to fold down. Does this seat even open fully?

Open the hood, remove 2 plastic pins & cover just below the windshield on passenger side. There should be a preformed long rubber gasket that diverts any water away from the cabin filter (regularly replaced) found underneath in the compartment & sometimes the rubber becomes dislodged when changing the cabin filter.

Check underneath the seat for an inline fuse. It is a glass type fuse in a fuse holder that you have to push and twist to get out.-----------------------------------------------------------------------------
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Before you do any of the expensive things disconnect and reconnect the wiring to the seat I had the same exact problem with my 2009 Chevy Impala and was ready to take it to the dealer when I disconnected the power cables to it and reconnected them I found that one of the Harnesses was loose and the problem was solved

take the panel off the other side door and have a look and compair the two, though there is a small part between the two mechanisms that maybe missing

honestly couldnt say without a look and a play with a hose pipe .

Try a slim jim first, down the side of the window. Or AAA or locksmith. If no luck, remove the seat first. Find the screws and bolts around the door handle and arm rest. Most Ford's have screws around the outer side of the panel. I don't believe your's does. The panel lifts or pops off. Once the panel is off, you can reach down and open the door. Just a note. I have done some to where the panel came out in pieces.

In your situation I think your best bet is going to be taking out the back seat. Luckily this is very easy and will allow you easy access to your truck and jumper cables. Okay in order to remove the back seat you will have to have a socket set. There should be 2 bolts holding the bottom of the seat down and you can find them on the floor on the front part of the rear seat. One bolt on the driver side and one bolt on the passenger side. After you get those bolts out you should be able to remove the bottom section of the seat. If you can not look for two more bolts on the back part of the seat. You will have to look between the back of the seat and the bottom part. After you take those two bolts out both parts of the seat should be free and you can remove them. I hope this helps.

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