Heated seat wiring

jjr197 · August 27, 2011, 18:21

The only good post I could find about this had dead photo links.

I have fitted the Waeco heater elements and now I need to wire it all in. I was going to take the power from the 12v lighter socket. It looks like I just attach the red AND orange leads to the socket's positive and black to earth. The black lead has a metal loop on it to allow it to be attached to something with a screw. Is this right? I always thought that you needed a positive, negative, and earth?

I'm not great with this sort of thing, but I wanted to do it myself.

Any electrically minded people able to help?

Cheers

Jimi

Anonymous · August 27, 2011, 21:33

earth and positive and you be fine however be best to use the seat bolts as a earth and personally a live from the batt these things do draw a fair bit of power

jjr197 · August 27, 2011, 22:27

Earth at the seat bolt, not a problem.
Power from the battery, is there an easy way to do it so that it goes off with the ignition?
I'm a muppet and I know i'll drain the battery by forgetting to turn the seats off! Lol

Cheers! s:D

s:D

wbarrwebster · August 28, 2011, 12:12

Hi,

I did this mod years ago so memory a bit hazy...
There are different types of connections, I remember from a post that some one else fitted the switches in the centre consul where mine are OEM to the left of the steering column.
Anyway, I certainly took power from the Battery and run the wire from the nearside of the passenger's seat, I also took switched power from the Cig lighter!

I don't use them a lot but it's a great mod and good upgrade IMHO.

One other issue, I did put some inline fuses in the Battery wire and the wire from the Cig lighter.

B

jjr197 · August 28, 2011, 14:48

Power from 2 different places?
I'm starting to feel out of my depth!

I know that I need 2 lots of power, seemingly either for each heat setting, or for each seat, but I assumed that it was either all power from the battery, or all from an ignition controlled source. Can I take it from the battery but still have it controlled by the ignition?

Jimi

Anonymous · August 28, 2011, 16:54

you will need a relay but what said above will be fine

jjr197 · October 9, 2011, 19:41

Right, finally got the elements wired in!
Took the power from the leads going to the ciggy lighter in the end. Works nicely and with plenty of heat too!
Just got to sort out mounting the switches now.

Does anyone know if I can get 3 position switches to go into the 2 blanks on the dash?

Jimi

Steve Green · October 9, 2011, 21:07

That sounds dodgy. Cigarette lighter is protected with a 15A fuse, or more correctly a 15A fuse protects the wiring to the cigarette lighter.
I have no idea what the rating of your heated seats are. I would have thought they would be marked.

Any switch you use, if you are taking the power from the circuit will need to be rated for 15A minimum otherwise there is a potential that it becomes the effective fuse.

Someone may remind me but I think the cigarette lighter turns off when the ignition is off. This is a good thing for your seats as there is some protection if you forget to turn them off.

It would be far better to switch the seat wiring with a relay so that the switch will not take the full current. The supply could then be wired back to the battery with its own fuse for the heated seats only.

jjr197 · October 9, 2011, 21:45

The seats draw up to 3.75a each, depending on which heat setting they are on, so 7.5a max. The two seat circuits also have their own 15a and 30a fuses in them, again depending on the heat setting.

It was the lack of a perm live that made me go from the lighter as I know I will forget to turn them off at some point.

To be honest, I thought that the wires running to the lighter looked a little feeble for 15a and I was tempted to put a 10a use in to replace the 15a one to give more protection to the wires.

wbarrwebster · October 9, 2011, 21:47

I would only repeat my previous experience, I ran constant live with inline fuse from battery to a relay, the switched live came from the cig lighter again to the relay. My switches are the oem type that sit in their proper positions to the LHS of the steering wheel.

Can I suggest you use a relay with in line fuse as your pulling a lot of power through the cig lighter, I realise it works but.....maybe I'm being a bit cautious.

B

Steve Green · October 9, 2011, 22:09

Quote from: "jjr197"The two seat circuits also have their own 15a and 30a fuses in them, again depending on the heat setting.

There is your clue, as clear as day. Another indicator would be to look at the size of the wiring tails on the seats. Everything back to the battery should be the same or larger, never smaller.
That means the switch should be able to carry the same current, those wont be that easy to find as conventional wisdom is to fit a relay.

In real laymans language, a small switch can be wired in just for the relay. this switch can be taken from a switched supply like the cigarette lighter or radio that is off with the key off. The relay, suitable for 30A should then be connected with wires, suitable for the load (30A) to the heated seat and battery, via a fuse.

What you have done might well work but is verging on the dangerous if there is a poor connection etc. etc. and we are sure you dont want to risk turning your car into a torch.

Steve Green · October 9, 2011, 22:13

Good reading is http://www.gtsparkplugs.com/WireCalc.html It even references a Toyota Document.

jjr197 · October 9, 2011, 22:39

Ok, I might just not understand this.

Cigarette lighter has a 15a fuse. One of the heated seat circuits also has a 15a fuse. Surely no problem there then?

The other heated seat circuit has a 30a fuse which if anything is redundant as there is already a 15a fuse in the line from the battery.

The max draw from the seats is 7.5a combined, nowhere near the 15a that the lighter is already fused to.

On this basis, how is there any risk?

I'm sure some of you guys understand this MUCH better than me, but I thought that my logic was sound.

Please help me understand this better! s:? :? s:?

Thanks

Jimi

roger · October 10, 2011, 13:30

Not getting into the current debate, don't pretend to know what you are all on about. s:bowdown: :bowdown: s:bowdown:

Having said that, I have the heated seats from a GB many years ago attached to the cigarette lighter with 2 small rocker switches embedded in the centre console. Don't know what rating the seats are, but the only problems I've ever had were wires coming loose.

Anonymous · October 10, 2011, 23:54

Quotethe current debate

See what you did there, Rog! s:lol: :lol: s:lol: