my dome light don't work neither one. I've heard the fuse panel is in the truck but I can't find it. all I see is what it looks to be two computer right in the back of the rear seats. Help

 

its under the back seat next to the battery.

 

thanks . but got no idea how to remove the seat. I was trying to pull it putting some pressure but got scared that something could brake.
what's the way to do it

 

HeyI think you may have two fuse panels, you should check if you have one under your hood aswell...
I have a 96 deville which has two fuse panels, and one is under the hood on the drivers side above the washer fluid reservior.

 

There is one under the hood, and another under the seat. You just pull up on the bottom of the seat cushion with a little bit of force and it will break loose. The only thing you have to watch out for is if you have heated rear seats (optional on the Deville, standard on DHS and DTS). Be sure the little wiring harness does not become unplugged when you move the seat up. If so, plug it back in when you slide the seat back in. To slide the seat back in, first slide in the back edge at an upward angle, push in a bit, then lower the front and push down. It will snap back into the mounts. I've done it a dozen times with no problem.

While you have the seat out, be sure you check the battery that is also located under the cushion. Make sure it is not leaking acid into the floor pan. I let mine go, and it ate a hole clear through the pan. I could see the asphalt, and even with the cushion in place could hear the exhaust. If you remove the battery, be sure to note how the vent tubes are arranged. Very important to get back in!