What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

Lemke seat heater wire routing?

Desert Rat

Well Known Member
Hey all, I'm planning to order a Lemke interior including seat heaters.

We all know the lead time for that sort of thing, so when I ordered my swatches, I went ahead and ordered the wire harnesses for the seat heaters.

Since I likely won't have the actual seats for the better part of a year, I plan to wire in the switches and just cap and stow the wiring connectors in the general location of where the seats will eventually plug in.

Does anybody have a picture or description of where that might be?

I'm guessing that running harnesses through the tunnel and up through the floor with plugs near the flap motor is reasonable, but I really don't know that for a fact.

I know that I could ask Robert Lemke, but I'd like to work on this tomorrow before they open up on Germany's Monday.
 
seat heaters

Put switches on panel, easy access, put relay under floor panels, heater connectors through riveted floor at junction of back and bottom cushion on the outside. Too busy in the center.


Keith Rhea
Rv7
 
Thanks Keith.

So to be clear, you're bringing the plug up somewhere in the ballpark of where I put the red x on the attached picture?

If so, I'll just cap and stow wiring under the floor and make the hole later after I get the seats, but that info is immensely helpful as I try to wrap up all the wire bundles.

regards,

Terry
 
These are the my Lemke seats received last July. I replaced the seat to harness connectors with .093 Molex pin/socket sets with panel mount housings on half.
3D printed a receptacle to hold the panel mount connector flush with the floor.

The controls /switches included use a dial to turn them on / off and set the power. There are no relays. The power goes into the control then to the seats.

I mounted the controls in a console that takes place of the mechanical trim location. It hides the connections nicely and mitigates the wires as only the power wires need to be run to them.

I get a very slight amount of noise in my headset in the low power positions. I doubt it will be loud enough to be heard with the engine running.
 

Attachments

  • IMG_1591.JPG
    IMG_1591.JPG
    277.2 KB · Views: 192
  • IMG_1604.JPG
    IMG_1604.JPG
    292.7 KB · Views: 213
  • img_1715.1 (4).jpg
    img_1715.1 (4).jpg
    287.1 KB · Views: 193
  • img_1715.1 (10).jpg
    img_1715.1 (10).jpg
    250.4 KB · Views: 209
Thanks for the input everybody.

FYI- If you option the round two position switches, they definitely have relays incorporated into the bundle. Interesting that the 5 position rotary switched do not.

I elected to go with the smaller 2 position switches due to panel space constraints, but I'm going to have to cut up and modify the bundles due to the way they're made. Don't have enough room to cram that many wires thru the spar
 
Hey- Just wanted to circle back to this with some info that might hopefully help others in the future.

After modifying this bundle, I had a heck of a time figuring out how to ops check it with a meter. To the point that I thought maybe I had gotten a couple of wires crossed up when I put it back together.

The schematic on the Lemke site was no help, because it depicts the 5 position rotary switches that, as previously mentioned don't utilize relays.

Ultimately, I figured this out, and here's what's happening;

The small round LO-OFF-HI switches are 20 amp switches, so they don't need a relay in this application.

When you select HI, power runs straight through the switch and into a circuit that parallels the seat and backrest heating elements, so they can both suck as many amps as they want, limited by the internal resistance of each element individually.

When you select LO, the relays change the current path so that the elements are now in series so they are effectively becoming their own resistor for a low heat setting.

I'm mentioning this here because it took me a ridiculously long time to figure this out, culminating with a light bulb moment when I found a schematic for an aftermarket car seat heater installation via google.

The design is kind of cool, but I'm more of an OFF or ON kind of guy. I've never had airplane seat heaters, but I mean, in my car, if it's cold enough for seat heaters, It's cold enough that I want them maxed out.

If I had figured out how this all worked a little earlier, I would likely have junked the whole wire bundle except for the switches and just gone with a simple one power wire to both elements in parallel and one local ground for a simple OFF-ON setup.

I just mention it here so that people can make an informed decision if they go with these seat heaters. Nothing wrong with the way it's set up if you want HI/LO heat, but there is a much simpler way to do it if you're more of an OFF-ON kind of guy.
 

Attachments

  • IMG_7148.jpg
    IMG_7148.jpg
    200.7 KB · Views: 180
Thanks Terry, that's good information. I received my Lemke seats this week, and I've been running this through also, trying to figure out how they work and where is the best place to put switches and connectors. I have the 5 position rotary dial though, but thinking about it I believe it would work in a very similar manner to the HI-LO-OFF switch, it just has a few more discrete positions.

To GeoffH - thanks for posting your photos. You've given me the idea to do something very similar with plugs in the seat base, and I think I will place the rotary dial switch in a position beside the lower seat cushion. I will still keep a switch on the panel so I can turn off heating in an emergency or when it's just not required.
 
A note to those with the 5 position dials... I discovered today that the lighting wire (the yellow one) on the controller is necessary. I think it provides power to a PWM style controller. Anyway, if that wire doesn't have power (I left it disconnected, not desiring lighting) it won't work. A rewiring of the controller and connector was needed to get it to work. I just tied it to the 12V power for the heater itself since my controller is on the forward seat pan just outboard of the seat bottom and dimming isn't a concern.

Also note, in the supplied wiring the power runs directly to the seats. The controller modulates the ground side of the heaters.
 
Back
Top