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Heated seat installation instructions - 2005 Pontiac GTO
These instructions should also work for '04 GTOs (and '06 GTOs if they don't change the interior.)

Note: These instructions are being provided by Ryan Workman (Corvetteforum.com: rworkman, ls1gto.com and gtoforum.com: rworkman98.) They are provided "as is", with no warrenty, express or implied. I assume no liability if you hurt yourself, others, or your car by following my instructions. Use at your own risk. I do not advise trying this installation unless you have at least some mechanical knowledge and experience. You can PM me with questions if you'd like.
GTOforum did not create and does not warranty the accuracy of this information.

1. Take off the trim around the seat. (This is easiest by moving the seat as far upward as it will go first.)
     a. The trim on the outside of the seat comes apart in two pieces.



     b. The trim on the inside front of the seat is removed by pulling straight forward.

     c. The trim on the inside rear of the seat is removed by pulling straight backward. Pulling it upward will break the trim piece.

2. Remove the bolts holding the seat in.
     a. Move the seat as far forward as it will go. Remove the 2 rear bolts with a ratchet.
     b. Move the seat as far rearward as it will go. Remove the 2 front bolts with a ratchet.
     c. Move the seat to the middle, and recline the seat back as far as you can.

3. Remove the seat from the car
     a. Disconnect the negative battery cable from the battery. (You won’t need power again until you are putting the seat back in the car. Disconnecting the power supply protects both you and your car.)
     b. Remove the two power supply plugs connecting the seat to the car.


     c. Put a towel over the door sill to prevent it from being scratched as you remove the seat.
     d. Pick up the seat, and carefully pull it out of the car.

4. Disassemble the seat.
     a. Remove the two screws holding the plastic piece that has the seat controls on it.



     b. Pull the plastic piece away from the seat.
     c. Disconnect the three plugs connecting the plastic piece to the seat.



     d. Remove the one screw holding the opposing plastic piece to the seat.

     e. Remove the four screws (two on each side) holding the back of the seat to the bottom. It will look like this when you're done.

5. Install the bottom heater element. (The bottom heater element is the larger of the two.)
     a. Turn the bottom seat cushion over


     b. Remove the plastic piece holding the leather into the seat cushion. There are four of these (one for each side). I removed 3 of them on my first seat, but later found out you really only need to remove the one on the front of the seat cushion

     c. Carefully separate the leather from the seat cushion material. The leather is Velcroed to the cushion foam along the seams. You only need to separate the seams about halfway down the sides and the one in the middle of the seat.

     d. Insert the bottom heating element in between the leather and the seat cushion foam. Remove all the paper from the top of the element, and place the sticky side toward the leather. I found it best to place the rectangular hole across the seam in the middle of the seat. That way, only a small portion of the heater is compressed by that seam. This situates the thin section of the heater element behind the seam (toward the back of the seat), and the main portion of the heater element toward the front of the seat. Then I ran the wires out the front of the seat on the side nearest the center console.

     e. Carefully re-Velcro the leather to the seat cushion. Then re-attach the plastic piece holding the leather to the seat cushion on the bottom of the seat.

6. Install the back heater element. (This is the smaller of the two heater elements.)
     a. Remove the back panel from the seatback. (This is the panel that has the large seat pocket in it.) To remove this panel, grip it from the bottom, and pull the bottom of the panel out. This will likely break the two white plastic pieces holding it on the seat, but this is unavoidable. If you pry the seatback out any other way, you’ll actually break even more pieces.


     b. Note the broken plastic pieces in the above picture. One plastic piece (broken into 2 pieces) is circled in red. The spot where it belongs is circled in blue. You should purchase 4 replacement pieces from your Pontiac dealer (or elsewhere) before you start this project. (You need 2 for each seat.) [GM Part# 92140918] I actually was able to re-attach mine by using a very strong plastic bonding glue, but I really should have replaced them. Now, mine are bonded to the seatback, so I’ll have a real problem if I ever need to remove my seatback again.
     c. Similar to step 5b, remove the plastic piece holding the leather to the bottom of the seatback. You only need to remove the bottom one in order to install the heater element.

     d. Insert the heater element, after removing the paper from it, with the sticky side toward the leather. I inserted mine lengthwise (with the widest dimension pointing up and down), and the wiring running down the side of the seat near the seam. My wiring comes out from the bottom of the seat, on the side nearest the center console.

     e. Reattach the plastic piece holding the leather to the bottom of the seatback.

7. Reassemble the seat, in reverse order of disassembly.
     a. Re-attach the back panel (using the two new plastic clips you purchased from Pontiac.)
     b. Bolt the seatback to the seat bottom. (Make sure your two heater element wires can reach each other. Now is a good time to connect them to each other (but not to the switch yet), and make sure they will stay out of the way, and out of sight when the seat is put back in the car.
     c. Screw in both plastic trim pieces. Don’t forget to reconnect the three electrical connectors.

8. If you are installing both the drivers and passengers side heated seats, repeat steps 1 through 7 on the other seat. (Note: You may want to perform steps 1-2 on both seats before going on to step 3. You need battery power for steps 1 and 2.)

9. Position the switches.
     a. I found the easiest place for my switches was the center console, in the same area as my traction control button.
     b. Remove the faceplate surround the T/C button. This can be removed by placing small screwdrivers between the piece and the molding around it, and prying very carefully. It will just pop out. (The actual TC button will stay in place.)
     c. If installing both drivers and passenger heated seats, drill two 13/16" holes next to each other in this plastic faceplate. Positioning of these holes is crucial. You want to leave slightly less than 1 mm between the side of the faceplate, and the edge of your hole. You also want to leave about 1 mm between the two holes. You have to set it up perfectly for both switches to fit,
     d. Disconnect the 4 wires from each switch. (You’ll have to cut the clear plastic on the ground wire, in order to disconnect it from the switch. The other wires can be removed just using pliers and a bit of pressure. Make sure not to break the wires or connectors. Also, make sure to remember which wire goes in each spot. If you reconnect them in the wrong location, your heater will not work.)
     e. Install the switches into the faceplate from the top. (I had to use my Dremel to create a very small convex section on the left side of my rightmost switch. This was necessary for them to fit next to each other. Measure everything carefully, so you do not have to remove more material than necessary.)

10. Running the wires and connecting electrical.
     a. Access your fusebox by pulling down on the trim piece below your headlight switch. The entire piece below your steering wheel comes down as one piece. Once it’s down, pop it off the left connector, and move it left to remove this piece from the car. Otherwise, it will be in your way.


     b. Remove the lid of your center console by unscrewing the two screws by the hinges, and pulling the lid backward.
     c. Remove the plastic piece on the back of your center console. (This is the piece that includes the rear heater vents and tiny compartment. There is one screw on either side of the center console near the rear. Unscrew these, then gently pull the plastic piece w/ the vents backward to remove it.

     d. Now, you need to run your wires, so you know how much wire you need. Run the red and black wires through your center console so that the plastic connecter is situated under where your seat will be. It is easy to run the wires underneath the console by gently lifting up on the trim where it touches the carpet. Make sure your plastic connector has enough room to reach the corresponding connecter on the seats when they are reinstalled. Remember that your seat will need to move in all directions, and still stay connected.
     e. Run the wires to the switches, by running them up from the bottom, through the little holes underneath the "traction control" faceplate.
     f. Connect the wires (in the correct order), to the switches, then reinstall the faceplate. Thread the wires up through the bottom of the console.
     g. Find the "accessory on" spare in your fusebox. (This is the empty spot, 2nd from bottom, in the middle row of fuses. It is labled as "Spare" on the diagram.)

     h. Buy a male connector to fit into this slot. I have included an example of two connectors. For mine, I had to cut off part of the connector, so it would be small enough to fit. If you find a small enough size connector, you may not have to do that. You should be able to find these at Radio Shack or elsewhere. (The connectors that come in the kit aren’t really the right type, but you may be able to get away with using the smallest brass one.)

     i. Solder this connector to a 6" piece of wire. Then pass this wire through one of the slots underneath the fusebox, so it sticks out behind the fusebox.

     j. Solder the other end of your 6" piece of wire to the two fuse holders included in the kits. (If you are only installing one seat, you will only have one fuse holder.

     k. Solder the other end of the fuse holders to the red wire. First, cut the red wire to size. You want some slack, so you can position it out of the way, but I only ended up using about half the length of wire provided in the kit. Make sure to wrap all your solder connections in a butt connector, electrical tape, or both. Obviously, you don’t want exposed wire or connectors to touch anything else on your car.
     l. Cut the black wire to size. Solder the two of them to one of the round connectors provided in the kit. Secure this connecter to a screw or bolt that has good contact with unpainted metal in your car, so you can complete the path to ground with minimal resistance. (Unscrew the screw or bolt, place the connector around the screw or bolt, then reattach.) [I used a screw up behind my fuse box near my brake pedal.]
     m. Secure all wires out of the way, so they do not interfere with pedal travel. I taped mine up near the fuse box. There was a nice little ledge that was perfect for this.

11. Reinstall your seats.
     a. Be careful when placing them back in the car. Do not pinch any wires or scratch your car door or dash.
     b. Place the seats over the anchor points in the floor
     c. Reconnect the electrical connections to the seats
     d. After both seats have reached this point, reconnect your battery.
     e. Connect the heater element connectors to the connectors attached to the switches, and the ones attached to the fusebox. Make sure your wires are in a good location. Make sure you can move the seat in any direction without pinching or stretching the wires or connectors. You may wish to secure them with the provided zip-ties.
     f. Screw in all 4 anchor screws.
     g. Re-attach the 4 trim pieces.

12. Reinstall your rear vents.
     a. Conceal all excess wiring in the area between the floor and where the rear vents will go back. There is plenty of room here.
     b. Reattach the plastic piece with the rear vents, taking care not to pinch any of your excess wiring. Screw the two screws back in.


     c. Reattach your center console compartment lid.

13. Turn on your car, and test your seats