Louisd75
Adventurer
By popular demand, here's a quick rundown on how I installed a set of WarmSeat seat heaters in my '02 Toyota Tacoma. I ordered the seat heater kit from www.JEGS.com, but if you search for WarmSeat heaters on the internet I'm sure you'll find other sources. I went with the waterproof model, which as you'll see was a good idea in theory, but not so good for my application. I'd have saved a couple of bucks if I went with the regular ones.
You'll need a pair of hog ring installation pliers and a pair of diagonal cutters for this part, along with whatever tools needed to remove your seat. For the electrical work, you'll need whatever connectors necessary to tie into your particular electrical system (I used appropriately sized ring terminals).
If you have a side airbags or airbags that are mounted in the seat (newer vehicles) you're probably better off taking it to a professional. If you've got an older rig or no airbags in your seats, carry on:
First up, remove the seat. Not too difficult, but be aware that there may be sensor wire connections you'll need to disconnect, like the seatbelt unbuckled warning light wire on the driver's side of the Tacoma.
Next up, you'll need to get the upholstery off of the seat. I decided to start with the bottom cushion, and in order to take the upholstery off, I first needed to remove the plastic trim. I can't really describe how to do that other than to say that it's sort of a pull/twist/shove all at the same time on the Tacoma. If you have a factory service manual, they usually have an exploded diagram of how things fit and what can be disassembled and reassembled. Here's a shot of the passenger side with the plastic cover removed, the bolts for the seat pan will be obvious since they do nothing other than hold the seat pan on:
Trust me when I say that you'll want to avoid hitting any of the recline levers while the seat is out of the truck.
So, now you've got the lower seat cushion off. Flip it over and have a look see at the bottom. It probably looks something like this:
Astute observers will note that the bottom of the seat is still attached to the frame in this picture. That's because it's the best picture I have of the underside. I was mostly taking pictures so that I could see how things were supposed to be when I put it all back together. The upholstery is held to the seat by small metal rings called hog rings wrapped around a piece of rod in the fabric. Using a pair of diagonal cutters, remove all of these hog rings around the perimeter.
Once all the perimeter hog rings have been removed, you can start removing the upholstery. You'll find that the top of the seat cover has more rods that are clipped onto rods embedded in the cushion with hog rings. The lower cushion on my truck had one rod going across the seat and two running parallel with my legs. Here's a view of one of the parallel upholstery tie-ins. You can see the hog rings (red) and the rod (green):
I snipped those last hog rings and removed the upholstery completely from the cushion. Now, it's time to get the seat heater ready for installation. The heater pad fits between the parallel upholstery tie-ins mentioned above, but you're going to have to get it to go underneath the rod that goes across the width of the seat. To do this, you'll need to cut some holes in the heater pad (see why I could have skipped on the waterproof ones?). This isn't a big deal so long as you DO NOT CUT the leads that run down the sides of the pad. Cut those, and the pad is no good. I marked out the leads and location of the fold that needs to go under the rod going across the width of the seat (believe me, it will all make sense once if you decide to take this on):
Here's the bottom heater sitting on the foam pad. The sharpie line marking the fold is pretty obvious. The other sharpie lines are the electrical leads that you're not supposed to cut:
Now, along the sharpie line for the fold you'll need to cut two holes about 1" diameter to allow the hog rings to pass through and hold the seat cover to the seat cushion. After I cut the holes I lined the edges with electrical tape to insulate them from the hog-rings. Then I put the seat cover on and hog-ringed it to the cushion, then began reinstalling hog rings in roughly the order I took them apart. This is where the pictures end. The hog-ringing wasn't difficult and the initial pictures were taken more as a reminder of where to put things in case I ran into a snag. Once the lower cushion was back together I removed the seat cover from the seat back. This was even easier. There was a clip along the bottom edge of the cover. Once I undid that, I was able to shimmy the cover up the seat back til I hit two hog rings going across the width of the back. Snipped those and that was it. I saw no need to remove the cover completely and I installed the seat back heater in the same manner as the seat cushion heater: cut a couple holes for the hog rings, cover the edges of the hole with electrical tape, install new hog rings, slide cover back down and fasten clip on bottom. I reattached the lower cushion to the seat and reinstalled it in the truck. I worked on the seats over two evenings. The first took about an hour, the second took about 30 minutes.
Once the seats were prepped, I started wiring up the the truck. The wiring harness looked to be decent. The instructions for wiring were anything but. I ended up drawing out the wiring harness just so that I could see what was doing what with the relay and switch. In the below drawing, the left side is what came from the factory. The white wire goes to a ground somewhere, the red wire comes from a source that is switched on with the ignition. I didn't like the idea of adding a potential 10amp load to existing accessory circuits that had 15amp fuses, so I opted to to a different route. To the right of the drawing you can see the addition that I made by installing a relay and a piggy back fuse. The relay closes when the ignition is switched on, providing power to the seat heater circuit. Not shown in the drawing is the supplied fuse installed between my circuit and the original circuit. There is an additional 20amp fuse between the fuse block and the relay. Also note that the drawing is for one seat. The other seat circuit also comes off of terminal 87 on the relay I added and is identical to what is already shown.
Once I figured out how and where I was going to make the connections, it was time to start actually running wire. I mounted the relays for each seat heater underneath the center console and ran the wires out the sides to the seat heaters and forward underneath the consoles to the switches. The switches are mounted on the trim below the ash tray:
The relay I added, along with the piggy back fuse and my aux fuse block are located under the driver side dash.
All in all I wouldn't say that this project was terribly difficult. There was definitely a bit of worry initially dealing with the seat upholstery, but in my case it all was very straightforward. I didn't do this project with the intention of also doing a write up. I would have taken many more pictures if that had been the plan. Unfortunately, I was in a bit of a hurry to get the job complete in time for a trip.
Hope this doesn't create more questions than it answers
You'll need a pair of hog ring installation pliers and a pair of diagonal cutters for this part, along with whatever tools needed to remove your seat. For the electrical work, you'll need whatever connectors necessary to tie into your particular electrical system (I used appropriately sized ring terminals).
If you have a side airbags or airbags that are mounted in the seat (newer vehicles) you're probably better off taking it to a professional. If you've got an older rig or no airbags in your seats, carry on:
First up, remove the seat. Not too difficult, but be aware that there may be sensor wire connections you'll need to disconnect, like the seatbelt unbuckled warning light wire on the driver's side of the Tacoma.
Next up, you'll need to get the upholstery off of the seat. I decided to start with the bottom cushion, and in order to take the upholstery off, I first needed to remove the plastic trim. I can't really describe how to do that other than to say that it's sort of a pull/twist/shove all at the same time on the Tacoma. If you have a factory service manual, they usually have an exploded diagram of how things fit and what can be disassembled and reassembled. Here's a shot of the passenger side with the plastic cover removed, the bolts for the seat pan will be obvious since they do nothing other than hold the seat pan on:
Trust me when I say that you'll want to avoid hitting any of the recline levers while the seat is out of the truck.
So, now you've got the lower seat cushion off. Flip it over and have a look see at the bottom. It probably looks something like this:
Astute observers will note that the bottom of the seat is still attached to the frame in this picture. That's because it's the best picture I have of the underside. I was mostly taking pictures so that I could see how things were supposed to be when I put it all back together. The upholstery is held to the seat by small metal rings called hog rings wrapped around a piece of rod in the fabric. Using a pair of diagonal cutters, remove all of these hog rings around the perimeter.
Once all the perimeter hog rings have been removed, you can start removing the upholstery. You'll find that the top of the seat cover has more rods that are clipped onto rods embedded in the cushion with hog rings. The lower cushion on my truck had one rod going across the seat and two running parallel with my legs. Here's a view of one of the parallel upholstery tie-ins. You can see the hog rings (red) and the rod (green):
I snipped those last hog rings and removed the upholstery completely from the cushion. Now, it's time to get the seat heater ready for installation. The heater pad fits between the parallel upholstery tie-ins mentioned above, but you're going to have to get it to go underneath the rod that goes across the width of the seat. To do this, you'll need to cut some holes in the heater pad (see why I could have skipped on the waterproof ones?). This isn't a big deal so long as you DO NOT CUT the leads that run down the sides of the pad. Cut those, and the pad is no good. I marked out the leads and location of the fold that needs to go under the rod going across the width of the seat (believe me, it will all make sense once if you decide to take this on):
Here's the bottom heater sitting on the foam pad. The sharpie line marking the fold is pretty obvious. The other sharpie lines are the electrical leads that you're not supposed to cut:
Now, along the sharpie line for the fold you'll need to cut two holes about 1" diameter to allow the hog rings to pass through and hold the seat cover to the seat cushion. After I cut the holes I lined the edges with electrical tape to insulate them from the hog-rings. Then I put the seat cover on and hog-ringed it to the cushion, then began reinstalling hog rings in roughly the order I took them apart. This is where the pictures end. The hog-ringing wasn't difficult and the initial pictures were taken more as a reminder of where to put things in case I ran into a snag. Once the lower cushion was back together I removed the seat cover from the seat back. This was even easier. There was a clip along the bottom edge of the cover. Once I undid that, I was able to shimmy the cover up the seat back til I hit two hog rings going across the width of the back. Snipped those and that was it. I saw no need to remove the cover completely and I installed the seat back heater in the same manner as the seat cushion heater: cut a couple holes for the hog rings, cover the edges of the hole with electrical tape, install new hog rings, slide cover back down and fasten clip on bottom. I reattached the lower cushion to the seat and reinstalled it in the truck. I worked on the seats over two evenings. The first took about an hour, the second took about 30 minutes.
Once the seats were prepped, I started wiring up the the truck. The wiring harness looked to be decent. The instructions for wiring were anything but. I ended up drawing out the wiring harness just so that I could see what was doing what with the relay and switch. In the below drawing, the left side is what came from the factory. The white wire goes to a ground somewhere, the red wire comes from a source that is switched on with the ignition. I didn't like the idea of adding a potential 10amp load to existing accessory circuits that had 15amp fuses, so I opted to to a different route. To the right of the drawing you can see the addition that I made by installing a relay and a piggy back fuse. The relay closes when the ignition is switched on, providing power to the seat heater circuit. Not shown in the drawing is the supplied fuse installed between my circuit and the original circuit. There is an additional 20amp fuse between the fuse block and the relay. Also note that the drawing is for one seat. The other seat circuit also comes off of terminal 87 on the relay I added and is identical to what is already shown.
Once I figured out how and where I was going to make the connections, it was time to start actually running wire. I mounted the relays for each seat heater underneath the center console and ran the wires out the sides to the seat heaters and forward underneath the consoles to the switches. The switches are mounted on the trim below the ash tray:
The relay I added, along with the piggy back fuse and my aux fuse block are located under the driver side dash.
All in all I wouldn't say that this project was terribly difficult. There was definitely a bit of worry initially dealing with the seat upholstery, but in my case it all was very straightforward. I didn't do this project with the intention of also doing a write up. I would have taken many more pictures if that had been the plan. Unfortunately, I was in a bit of a hurry to get the job complete in time for a trip.
Hope this doesn't create more questions than it answers
