First off, I bow down to all those before me. The stickies on this forum are a godsend. I've done a couple of small mods, but this is my first attempt at a big mod, one that hasn't been covered. Heated seats are the one creature comfort I definitely think are worth it, and I decided to give it a try on my own. I used tricks from other installs, and it worked! I have stock seats that get hot in 2 minutes. Once my remote starter is in, I'll have hot seats the second I climb in.
Took me a few hours/beers to do it all, others will be much quicker with some experience. Still need to get a better switch, and I'm considering the OEM seat heater switch from the 4runner, but that will cost more that the whole setup does.
This will be edited tonight as I upload the pics, be patient...
This is the whole package I got in the mail, about $100. Followed the link from a prior thread on heated seats to find a company. There are loads out there. I chose a single seat, since it says you can have problems with the passenger side airbag sensor. Comes with everything shown, incl. a switch. Instructions are basically useless.
Step #1: Take out the seat. No way around it, but this is actually really easy. Don't waste your time trying without doing this. I did for you. 4 bolts on the floor. Simple. They're on tight, use a rachet. The two bolts behind the seat are covered by a plastic cover. A flathead screwdriver pops them up and back. Tip the seat back once unbolted, and unplug the 3 cables. I have airbags, you might have less cables.
Next, take the seat out and turn it onto its side:
The large backing piece comes off easily, by unhooking the two black elastic bands attached to the two large white clips. This shows the second one coming off:
The next thing that needs to come off is the J-clip holding the back of the bottom seat cover to the springs underneath. They are just long U-shaped plastic hooks that attach to the black wire springs holding up the white "fluff". They pop off if you create a little slack in the fabric. My pinkie is pointing to one of the wires it was attached to.
Next comes the hard part. There are long wires with hooks on either end that thread through the fabric, holding it in place. There is one for the bottom cushion and one for the backrest. This is what prevents you from simply sliding the carbon fiber sheets under the fabric into its final resting place. This is what it looks like when removed and one hook is bent straight:
Basically, I grabbed one hooked end of the wire, and bent it nearly straight with pliers. I then grabbed the other hooked end and pulled it right out. This releases the backside of the fabric. Here is a pic of the wire half out of the backrest part:
As you can see, it slides through folds in the fabric, as well as several D-rings, to hold it tight in place. It's easy to pull the wire out and release the fabric; the hard part is getting it back in after.
Once the fabric is released, it can be pulled through the sitting-surface side. Reclining the seat makes this easier. There is then a space to slide the carbon fiber sheet inside. Take the smaller sheet and slide it from behind the seat up inside and between the foam and the fabric on the backrest. It fits perfectly if you have the brand I got.
The bottom seat is harder. To make it easier, you could just cut the sheet and use half, or find a smaller pad. Then you could do the same process on the bottom seat, i.e. slide it from behind into place, with the wires coming out the back.
What I did was remove more of the bottom covering, so that I could slide the entire long heating pad onto the bottom seat. The problem is that the fabric is tethered down halfway, and you need to release more fabric in order to be able to slide the entire sheet to the front of the seat. I pulled more J-clips off from the side of the seat to release the fabric there. It is also bolted down with a clip under the large plastic covering. The large cover comes off with a single phillips screw from the back. The clip pops out from inside. Sorry, no good pics.
The large bottom sheet is fed from behind between the fabric and the foam in the same way as the top. Once you reach the tethered part, it seems you can't go any further. After releasing more fabric along the sides to the front, I was able to force the sheet under the tethering and all the way to the front of the seat. Replace everything in reverse order. Don't forget the annoying thick wires. The hardest part is feeding them back through the fabric and D-rings, and then re-forming a loop to lock it in place.
This is how it looks with the sheets in place and the wires coming out the back of the seat:
You can see the thick black cord going up between the fabric and foam for the bottom section. You can see the other black cord heading up to the backrest. The yellow cord is seen going up into the backrest as well for the airbags.
The black J-clips are then reattached, the back cover elastic bands are replaced on the white clips, and the cord is attached to the rest of the wiring harness. I zip-tied this right next to the other OEM cords on the bottom at the connector, so that all 4 could be easily disconnected in the future.
The final wiring to the switch is the easiest part, and similar to any other setup. I stuffed the wire under the center console without removing it, and then up under the steering column. Red power wire was attached to a spade and put into the Lefthand side fuse box, in an acc-powered location (5th from right, center row). It is already fused. Ground was placed in the bolt behind the brake. The switch was just pulled through the fuse cover for now. It's a great little round switch with red and amber lights for low and high. I might mount it on an OEM blank switch, or use a 4runner switch.
Sorry if this is clear as mud. Some is hard to describe, and of course I didn't take enough pics. But it was fun, it didn't take too long, and it totally works. And I'm no genius at this stuff. On hot, I feel it at one minute, and it's toasty at 2. On low, it's pleasant. It goes from the back of my knees to the middle of my back. I think it's actually better than my wife's 4runner seat heat. At this point, definitely worth the money and time. I could yank them out to restore to original if needed.
Let me know if you have any questions. Once the seat is out, it's a simple little puzzle. Good luck!
