diy heated seats

[Eugene]

Here is a write-up of how i installed heated seats in my white i-miev:
http://i-mievlog.blogspot.com/2013/01/i-miev-diy-heated-seats.html
In a nutshell:
1. buy heating elements on e-bay
2. Phase 1: install heating element for the backseat of the driver's seat. Reuse existing wiring. It really makes a difference and is fastest way to enhance winter driving.

3. Phase 2: install passenger-side seat. Tricks are to find a + and install the switch/regulator
4. Phase 3: install driver-side regulator

It took ~80$ and 2 weekend evenings, in between infant feeding and sleeping sessions....

 

[Llecentaur]

Thank you very much for the information. I might go half way there as I bought seat covers and might just fix the heating elements over the seat covers without glueing them.

Do you think that the driver's seat heatinf wire can withstand also providing current to the passenger seat ?

 

[Vike]

I've always thought the lack of front passenger seat heating is a serious oversight, given how tolerable I find it to keep the cabin fairly cool with my seat heater on. But I'm not much interested in hacking around at this juncture, hoping there's a quick and dirty passenger seat solution for our relatively short cold snaps.

To go much lower effort, is there anything wrong with using an off the shelf heated seat cover plugged into the 12V outlet? One example I looked at said it drew 42W, not sure if that's typical. That's obviously a heck of a lot less than the cabin heater; while I realize the cabin heater draws from the traction battery and not the 12V system that would be used to power the accessory seat cover, I'm sure the driver's seat heater is running off the 12V system as well. The main concern I'd have is that there might be a problem drawing that much through the 12V accessory outlet in particular, or even that the reason for the single seat heater was to limit the load on the 12V system in the first place (who knows?).

Any thoughts? Anybody else trying/tried this?

 

[Eugene]

Llecentaur, That is definitely the less intrusive path, an if you have tight-fitting covers, that would be great. You can attach the heating elements to the cover itself, not modifying the seat.
I think the wiring harness can handle it, given the fact that the standard heated seat switches off periodically on its own. If the wire heats up, it has time to heat down.

 

[PV1]

42 watts is only 3 or 4 amps at 12 volts. The outlet is fused for 15 amps, so as long as the plug is in the outlet with a good connection, you shouldn't have a problem. The radio uses more power at high volume. Although, I would have some concern over running both seat heaters, the rear window defroster, and the heated mirrors all at once, but I don't know the specs on the 12 volt system completely.

 

[Eugene]

I'm sure the driver's seat heater is running off the 12V system as well. The main concern I'd have is that there might be a problem drawing that much through the 12V accessory outlet in particular, or even that the reason for the single seat heater was to limit the load on the 12V system in the first place (who knows?).

The standard driver's seat is running of 12V system. The accessory outlet can handle 10A, which is 120W. So 48W for the snap-on heating element is fine.

 

[Llecentaur]

Thank you all for feedback.

Eugene, good idea to attach the heating piece to the seat cover. That is the power of lateral thinking. If you are interested by the seat covers I have found some nice on measure ones made in France. see related post.

Now I need to order a two piece heater in order to add a back to the driver's seat and at least a sitting heater for the passenger seat. Hope they will get over before winter ends :roll:

 

[sarahjoe]

hey
thanks for sharing the information i really like it

 

[Tiborx8]

Guys,

don`t try to rip the seat cover off as suggested in this thread!!!

Under the seat cover there is a 10 mm soft foam, under that there is the seat occupancy sensor. This sensor measures the weight of the driver/passenger and the airbag is switched on/off according to the info - so ruining the occupancy sensor means that you compromise the airbag operation!

How to do it properly:
1. you need to start to remove the seat cover from the back of the seat. You need to progress from the back towards the front of the seat.
2. use Xylane - apply it to the seat cover both over and under it by spraying or using a brush. Apply-pull-apply: proceed slowly, cm after cm. This way you are able to remove only the cover but not damaging the foam underneath - so leaving the occupancy sensor alone. For a proper job, you need to remove the cover from the horizontal part of the seat completely.
Expect three days while the xylane smell goes out of the seat/car, and proceed with the heating element install only after.

2. as the cover is a relatively thin material, the heating pad edge is clearly visible if you just put back the cover or if you glue back. You can also feel the element when you touch the fabric as it is much harder and different surface than the foam around it.
The proper way for reassembly:
1. buy a 5mm soft foam at a carpet/upholstery shop and lay it over the whole horizontal surface of the seat - this way the heating element will not be visible and you will not feel it when you touch the cover.
2. cut the foam to shape, following the seat, than use a fabric glue in spray form (you can also buy it in a carpet/upholstery shop) and glue the 5mm foam on the seat. Than glue the cover on the foam. It is better to spray the cover very little as the glue can penetrate through the material, so it is better to spray the foam more. In case the glue comes through the material, you can use a cloth with xylane to remove it - but use it gently as it can also dilute the glue under the fabric, which you don`t want.
Leave the seat for 24 hours to dry, do not sit on it during this time.

I did the passenger seat last week. My seat occupancy sensor still works fine and by the look and feel, you cannot feel the heating element.

As for the wiring:
You don`t need to drill through the firewall! Only thing you need is a mini fuse separator - so that you can put two fuse into one fuse slot. The fuse box is under the steering wheel (left hand drive model). I divided the cigarette lighter fuse into two as we barely use it. the original fuse is 15A, now I added a 10A fuse for the cigarette lighter and another 10A for the passenger seat - although as i measured, it takes less than 5A so I may change the fuse to smaller. As a ground point you can use the bolt under the fuse box.

I also bought a cheap 12v thermostat - I set the temperature around 38 degreed celsius so it feels worm but not too hot.

DO it at your own risk. It is not a very difficult job but you need to concentrate to every step.