How to remove REAR interior door panel 96 DeVille? Problem is to gain access to chrone window sill strip on exterior. Apparently a fastener/clip has popped off and chrome strip is sticking up on end closest to front seat. (Rear driver's side door) We have disasembled restored many 60's classic Mopars, but do not want to damage anything on this Cadillac, assuming that the assembly is much different. Thanks, Steve roberts

To remove the door sill panels on a 2009 SL550 Silver Arrow, you can follow these general steps:
1. Gather the necessary tools: You'll need a flathead screwdriver, a trim removal tool (optional but helpful), and a flashlight.
2. Open the car door: Ensure that the door you want to work on is fully opened.
3. Locate the door sill panel: The door sill panel is the strip located at the bottom of the door frame, where you typically step in when entering or exiting the vehicle.
4. Look for screws or fasteners: Inspect the door sill panel for any visible screws or fasteners that may be securing it in place. If you see any, use a flathead screwdriver to remove them.
5. Use a trim removal tool: If there are no visible screws, gently insert a trim removal tool or a flathead screwdriver between the door sill panel and the door frame. Be cautious not to scratch or damage the surrounding area. Apply gentle pressure and work your way along the panel, releasing the clips that hold it in place. The number of clips may vary depending on the vehicle model.
6. Apply even pressure: Once you have released the clips, the door sill panel should be loose. Apply even pressure with your hand and lift the panel upwards to remove it from the door frame.
7. Disconnect electrical connections (if applicable): If your vehicle has any electrical components, such as illuminated logos or lighting on the door sill panel, locate the electrical connectors and disconnect them before fully removing the panel.
8. Repeat the process for other doors (if desired): If you want to remove the door sill panels from other doors, follow the same steps for each one.
Remember to exercise caution and be gentle when working on your car's interior to avoid causing any damage. If you're unsure or uncomfortable performing these steps yourself, it's advisable to consult a professional or refer to the vehicle's user manual for specific instructions tailored to your car model.

Remove the door opening weather-strip. Refer to Door Opening Weatherstrip Replacement in Doors.
Remove side sill trim plate. Refer to Door Sill Plate Replacement in Interior Trim.
Remove the lower quarter panel trim. Refer to Rear Quarter Trim Panel Replacement in Interior Trim.
Remove the center pillar upper trim panel. Refer to Center Pillar Upper Trim Panel Replacement in Interior Trim.
Remove the quarter upper trim panel. Refer to Rear Quarter Upper Trim Panel Replacement in Interior Trim.
Remove the center pillar outer applique. Refer to Center Pillar Applique Replacement in Exterior Trim.
Remove the roof drip molding. Refer to Body Side Roof Drip Molding Replacement in Exterior Trim.

Important: It is necessary to use new nuts when reinstalling the quarter window.
Remove the nine quarter window nuts (1), securing the quarter window assembly (2) to the body opening.
Caution: When working with any type of glass or sheet metal with exposed or rough edges, wear approved safety glasses and gloves in order to reduce the chance of personal injury.
Important: When removing the quarter window from the body opening make sure that the attaching pins are clear of the outer body.
Remove the quarter window (2) from the body opening.

Remove the rear seat cushion. Refer to Rear Seat Cushion Replacement in Seats.
Remove the rear seat back. Refer to Rear Seat Back Replacement in Seats.
Remove the door sill plate. Refer to Door Sill Plate Replacement .

Remove the 3 quarter trim panel retaining screws (1).
Starting at the lower edge of the trim panel and moving alternately clockwise and counterclockwise, pull outward on the trim panel to disengage the eight rear quarter trim panel attaching clips (2).
Remove the quarter trim panel from the vehicle.
Remove the 4 radio speaker grille speed clips (1), securing the speaker grille.
Remove the speaker grille (2).
Remove the rear quarter trim panel insulator (1), from the back of the quarter trim assembly (2).
Remove 7 rear quarter trim panel armrest retaining clips (1).
Remove 7 rear quarter trim panel armrest retaining nuts (2).
Gently pry the quarter trim panel armrest insert assembly (3), away from the rear quarter trim panel and remove.

You mite look for a video on youtube !

It is located behind the right rear quarter panel , In the back right of the interior !
Remove the right rear quarter trim panel. Refer to Rear Quarter Trim Panel Replacement - Right Side in Interior Trim.
Removal Procedure

1. Remove the rear seat. Refer to Rear Number 2 Seat Replacement or Rear Number 2 50-50 Seat Replacement in Seats.
2. Remove the Third Pillar trim panel. Refer to Third Pillar Trim Replacement .
3. Remove the garnish molding. Refer to Body Rear Corner Garnish Molding Replacement .
4. Remove the door sill plate. Refer to Liftgate Door Sill Plate Replacement .
5. Remove the quarter panel trim screws.

A lot involved in this but not to difficult !

1. Remove the rear door sill trim plate. Refer to Front Side Door Sill Plate Replacement or to Rear Side Door Sill Plate Replacement .
2. Remove the lower rear seat belt cover and bolt.
3. Remove the trim panel from the vehicle.

Remove the sill plate. Firmly pull the sill plate up and out from the retainers.
Remove the sill plate from the vehicle. Start from the front of the door sill. Use a flat-bladed tool in order to pry the door sill plate.
Rear Side Door Sill Trim Plate Replacement
Use a flat-bladed tool in order to pry the door sill plate. Remove the sill plate from the vehicle.
Body Rear Corner Garnish Molding Replacement
Remove the rear upper garnish molding. Refer to Rear Upper Garnish Molding Replacement .
Pull down on the upper corners of the garnish molding in order to disengage the retaining clips. Pull in order to disengage the remaining retaining clips. Remove the rear corner garnish molding from the vehicle. Inspect the rear corner garnish molding for broken or missing retaining clips. Replace the retaining clips as needed.
Good Luck ! Fun job !!!!!

Door handle fasteners are accessed from inside the doors so you need to remove the interior door panels. The door handles are then usually held on by clips or slides which are rather awkwardly positioned behind the door structure.

1. Remove the front door trim panel.
   

1. Position aside the front door watershield to gain access to the exterior rear view mirror control switch electrical connector.

4.Disconnect the exterior rear view mirror control switch electrical connector

as you see you have to remove the door panel to have access to the electrical connector in case that you dont know how to do it here are the instructions

NOTE: Left front door trim panel shown, right front door trim panel similar.

1. Remove the sail panel.
   
   • If equipped, disconnect the electrical connector
   
   
2. If equipped, lift up and remove the exterior rear view mirror control switch panel.
   • Disconnect the electrical connector.

1. If equipped, lift up and remove the window control switch panel.
   • Disconnect the electrical connector.

1. If equipped, remove the window regulator handle.
   1. Position the window regulator handle cover aside.
   1. Remove the window regulator handle screw and regulator handle

5.Remove the door trim panel center screw cover
6.Remove the 2 door trim panel center screws
7.Remove the 2 door trim panel lower screws

1. NOTICE: Do not pull directly outward on front door trim panel as damage will occur.
   Remove the front door trim panel.
   • Lift upward to remove the front door trim panel.

1. NOTICE: Insert the lower panel tabs first or they can break when installing the front door trim panel.
   To install, reverse the removal procedure

well with your engineering experience you should have been able to figure out the latch assembly is not the problem!Did you even check the rocker lock switch with a test light to see if it is ok,If you had power rocking the the switch to lock,then with the test light rock it the other way and check that side for power,Then if you had power on both sides you follow the wires to the solenoid
that activates and pulls a rod "which is attached to the latch assembly" and does the locking.

I hope this helps , easier done than said :)
1- Remove door latch bezel. (handle) 2- You will find door trim panel retaining bolt , remove it. 3- Remove the door pull handle screw cover. 4- Remove the door pull handle retaining screws. 5- Detach the interior door trim panel ( to make removal easy , release clip by lowering glass and pressing case inwords) 6- Disconnect the door trim harness electrical connector. 7- Remove the door trim. 8- Disconnect the driver door module electrical connector 9- To install , reverse removal procedures

I just removed the passenger side door panel with two long screw drivers, a putty knife and an eight mm socket on a quarter inch drive ratchet. First of all I did NOT have to remove any trim or the door handle which stays attatched to the panel. I use the putty knife to protect the paint from being scratched by the screw drivers. Insert the putty knife, ( started at the bottom) outer edge. Next insert the screw driver on top of the putty knife and pry a little to create a gap. Now insert the other screw driver near the first one and pry. It will take some effort to pop the plastic fastener but that is what holds the panel on and there are several of them so just work your way around. I stuck a 2X4 mid way between the panel and door so I could see and gain access to the two 8 mm nuts holding the arm rest secure. I removed these screws from inside or inbetween the door and panel so no damage or removing the arm rest from the dor panel. Use a flash light to spot the nuts.After they are removed and all the plastic fasteners are pried out ( there was a stubborn one for me on top near the door lock) then pull UP on the panel to clear the window sill. Pull up and out at the same time and it should come out. Be patient because they are fairly secure and there are several of them.

You'll need to remove screws that are by the door handle, arm rest, under door and side of door and then gently pull back on the panel as there will also be retaining clips attached and you don't want to break them. You'll need to lift the door panel upwards in order to get it off the window ledge. If needed, you can pull back the weather seal (can't reuse it, but it's not that important) and you will be able to access everything inside the door

You will need to remove the door panel to gain access to the handle. Roll the window up or down as needed to get to the nuts that attach the handle to the door. You will also need to remove a rod the goes to the door lock. You will see the rod after the door panel is removed. Good luck.