The DeLorean seats can be quite cold in the winter, especially when you live in the north. Heated seats can be help make those cold mornings more bearable.
These particular instructions were originally written by Joe Angell and was initially based on his experiences, but others may have since made contributions, corrections or additions.
Choosing a Heated Seat Kit Edit
There are various retrofit heated seat kits available, and many can be found using a Google search. When choosing a kit, you really just need to make sure it will fit within the confines of the DeLorean's seats. The rest of the options are up to you.
After some brief research, I went with the Peak Deluxe Carbon Fiber Dual Temp Universal Heated Seat from Sports Imports Ltd. Kits for two seats cost around $175 USD. They seem to have upgraded the kit since I got them, as the link above is for the newer waterproof seats. I believe the leather seat covers protect them pretty well.
This particular kit includes two pads for each seat. The 9" by 15" pad is for the bottom of the seat, and the 9" by 18" one is for the back. These pads can be cut if they are too long, but I didn't need to do that. Each seat has two temperature settings controlled by a three-way switch with an indicator LED. The low temperature is from 110 to 115 degrees Fahrenheit, while the high setting runs at 120 to 125 degrees Fahrenheit. In use, this means they are quite hot, even on the low setting, and are easily felt through coats and other thick clothing. The electrical connection is a simple two-wire setup, with one going to ground and the other going to a 12v source.
Tools and Parts Edit
- Heated seat kit(s)
- Socket wrench with an 8mm socket
- Allen wrench, 8mm
- Philips screwdriver
- Wire cutters
- Two pair of needle nose pliers
- Crimp tool
- Ring-style wire terminals
- Tape, glue or similar
- Replacement hog rings
- Hog ring pliers
- Extra M8 washers, for re-installing the seat
Installing the Heating Pads in the Seats Edit
The first step is to remove the seats from the car. There are four M8 lock nuts holding each to the car. They extend right through the floor, and can easily be removed with a socket wrench once the car is raised up. These bolts themselves are press-fit into the rails, and don't need to be removed. I managed to strip most of the bolts on the drivers seat and did eventually need to replace them, though.
Once the seats are out, remove the cover on the back of each. These are held on with two philips screws at the base of the seat back, as well as guide clips on the left, right and top edges. Once unscrewed, the cover can be slid downward, then bowed and pulled out to detach the cover's guides from the seat itself.
You will also need to remove the rails from the bottom of the seats. These rails allows you to slide the seats forward and backwards. Each is held on with four M8 cap screws, and can be removed with an allen wrench. You'll need to slide the rail in order to access all of the screws.
If you need to [[Recovering Seats|recover your seats], now is a good time to do it. I managed to install the heating pads without completely dismantling the seats first, so I will outline that process here. The goal is to slide the heating pads between the seat covers and the seat pads. This requires removing many of the hog rings that hold the seat covers onto the seats.
There are two ways to deal with the hog rings. I did it the hard way, which is to use a two pair of needle nose pliers to bend each ring apart. I then reused these when putting the seat back together, although I broke a few of the rings in the process. This is a slow process, and takes much of the installation time.
The easier way is to get more hog rings, which you can then install with hog ring pliers. Remove one hog ring and bring it to an upholstery shop so they can match it up. You can then cut the remaining hog rings with wire cutters.
Once you have removed the seat covers, you'll have enough access to slide the heating pads between the seat pads and the covers. You'll need to experiment with angling the seat so that you can slide the pad between the seat. It may be a tight fit. Make sure that the pads lay flat, that they are not creased or folded over each other, and that they are the correct way up (they should be labeled). The cords for each pad will stick out the back of the seat.
You can now re-install the hog rings using the existing holes in the covers. Either bend the originals back in place with two pair of needle nose pliers, or use new rings and hog ring pliers.
The seats can now be re-installed in the car by reversing the removal instructions. First re-attach the rails, making sure that they line up properly. Next re-mount the seat back cover. Putting the seats themselves back in the car can be a little tricky. They do not sit flush on the floor, as this would impede the movement of the sliding rails, making it very difficult to adjust the seats. There should be a short stack of washers or stand-offs that the seats rested on. If not, you can get some M8 washers and glue or tape them in place. You just need enough washers so that the rail's adjustment lever clears the floor. You may find it easier to tape or glue the washers onto the seat bolts first. Make sure to use the same number of washers for each of the four holes so that the seat sits level once installed. Once the seats are on the washers, you can use the 8mm socket wrench to secure them and lower the car.
I chose to install the heated seats just in front of the power window switches. This gives the installation a fairly clean look and makes the switches easy to access, but does require modifying the trim for mounting. You may want to place the switches elsewhere if you do not want to modify the stock interior.
To help run the wires for the switches, I first removed the power window switch and dummy switch on the driver's side. I then removed the ash tray (it just pops out) and the two screws that secure the small tray at the back of the arm rest, removing it as well. This gives just enough access to run the wires without having to dismantle the entire arm rest.
Before you run the wires, you'll need to drill the holes for the switches themselves. As you can see from the picture, I didn't do a very good job on my first switch, but I refined the processes for the second one and got much better results. The issue at hand is that the trim piece is metal, not plastic. There isn't much give, so you need to get the holes very close to the diameter of the switches. Furthermore, each switch has a small notch sticking out so that it won't rotate when installed.
I found that the best thing to do is to drill a hole that is a little too small, and slowly widen it with a Dremel until the switch just fits. It's easy to widen a hole that is too small, but you're out of luck if you make the hole too big, so go carefully. The Dremel or a small, stiff file can also be used to notch the hole so that the switch fits properly and securely without rotating. If you do not notch it, the switch will not fit and it will seem like the hole is too small. Do not widen the hole; just add the notch.
Below the metal is some foam padding. You'll need to cut this away with a knife so that the switches can fit, and so you can run the wires out the back of the arm rest.
Once the holes are ready, you can snake the wires through it and out the back of the arm rest. This is kind of a pain, since the connectors on the switches are somewhat large. They will fit through the switch holes, but it may be difficult to snake them between the frame and the arm rest, but it is possible; you just have to be patient. It may help to run a guide wire through from the back of the arm rest, tie it to the connector, and pull both back through the arm rest. You'll need to poke at it with pliers or a screwdriver to keep it from getting snagged as you drag it backward.
If you want to make this job a little easier, you can cut off the connector a few inches from the end (leaving plenty of excess wire before and after the cut), then run the bare wires through to the back of the arm rest. Without the connector in the way, the wires can more freely move through the confined space, saving you quite a bit of time and aggravation. You can then join the wires to the connector again with normal butt or blade electrical connectors and a crimp tool.
Each seat has a red wire and black wire that need to be connected to a 12v source and ground respectively. Optimally, this should be an ignition-switched 12v source, as the high draw of the seats can quickly drain your battery if you leave them on when the car is off. In my case, I had already run a dedicated fuse box for other additions, so I was able to add the seats wiring to that. This was connected directly to the positive battery terminal with a heavy wire, passing through a relay that itself was energized by the accessory relay in the relay compartment.
An alternate high-amp 12v source is the large bundle of wires behind the backboard of the parcel shelf, above the relay compartment. Accessing this requires removing the four cargo net hooks with a philips screwdriver and lifting the board out (remember that there are two short and two long hooks when remounting the backboard; the long hooks go on the ends and the short hooks go in the center). The large screw with the thick brown wires going into it is the main distribution point for positive voltage in the car, and can easily be tapped into by adding a ring-style terminal to the 12v end of the wire. Note that you will still likely want to switch this with the accessory relay by running the red wire through another relay to the 12v distribution point, where the relay is energized when the accessory relay is live. There are numerous grounds that you can connect to here as well; the ground does not need to be switched. See the article on adding electrical accessories for more information on setting up ignition-switched additions.
Each heated seat uses 4 to 5 amps of power, and should be fused appropriately. For simplicity, you can connect the red wires of both seats to a single 10 amp fuse in an inline fuse holder.
Most of the wires can be hidden by running them behind and vertically carpeted area behind the seats. Simply pull up the carpet from the bottom and slide the wires in. You may have to flex out the center vinyl trim between the seats to pull the carpet out enough to run the wires.
Connections and Testing Edit
After everything is installed, you simply need to hook it up. The heating pads plug into the wiring harness, which in turn connects to 12v, ground and the switches. The harness cables are rather thick, but you can tuck the harnesses behind the seats, or possibly under them. If your kits came with extra extension harnesses, you won't need them; those are mostly for installing the kit in larger cars or in the rear seats. Even without them, you'll have plenty of slack in the DeLorean.
To test the seats, put the key in the ignition and turn it to the accessory position. Switching a seat to the low setting should cause the LED on that switch to glow green, while the high setting should cause it to glow red. Turn the car off, and the LED should go off. Start the car and turn on the seats. It'll take a few minutes to warm up. There will be no mistaking it -- it will be quite hot to the touch, not just a little warm.
If all went well, you now have nice, hot seats for the cold mornings.