Location of a +12V wire at rear seats/trunk for inverter?

[ThinkPad]

I have a 12V > 230V inverter that i would like to use during holidays and such. Unfortunately my 2006 Yaris only has a cigarette lighter outlet underneath the cooling/heating knobs.
Would have been nice if it had a secondary outlet available at the rear seats or in the trunk, but it's not there.

My Yaris has a towhook and electrical outlet for the lights of a trailer (7pins EU system) but i'm not sure if it carries a +12V. Some diagrams say that it has a constant voltage pin (for running a refrigerator in your caravan while driving for example), but later on it was changed to drive the foglight of a trailer.
I will get my multimeter and see what it carries and if it is a constant voltage, see if i can tap into it underneath the carpet of the trunk.

But should it not be available, is there maybe a different wire running to the back, to tap into that can handle about ~10A max. ? I prefer a wire that is turned on/off with the ignition.
I searched for a wire schema of a 2006 Yaris, but couldn't find it.

I also thought about soldering a wire to the cigarette lighter outlet and running it to the trunk, but that involves quite some work by lifting carpets and such.

[Kar98]

Man, the cigarette lighter outlet in a Yaris can't even power an actual CIGARETTE LIGHTER, much less anything other than a phone charger or a GPS.

[ThinkPad]

What fuse is it by secured?

I had a look at the towhook wiring, it was nicely connected with plugs that connect to the original rearlight plugs. It is a Toyota branded knob, made by Brink. No shabby soldering or so :)
But the continuous voltage pin i don't understand. With the key on ACC, it had no power. When i turned the lights on, it had +12V. But when i turned the rear foglight on, the power went away. I don't know where it is connected to. Not suitable to tap into anyway i guess.

I was hoping to find some suitable wire before i leave on vacation. But i think it is better to grab a wire directly from the battery and use that for the inverter. But that will be something for later, don't have time for that anymore.

[WeeYari]

You could run a wire direct from the battery and run it along the underside of the car. Zip tie it to the brake lines, and fish it back up into the rear under the tail lights. This is what I had to do with trailer hitch wiring on one of my vehicles that did not draw its power from the lights.

[ThinkPad]

No flame intended, but that sounds like a really shabby solution

I think i will mount the inverter under the passenger seat and run a wire from the battery through the firewall, behind the radio and then under the carpet along the transmission tunnel. Switching the power with a relay connected to the lighter positive or something.

[WeeYari]

Originally Posted by ThinkPad

No flame intended, but that sounds like a really shabby solution

Step 7 http://www.etrailer.com/instructions.aspx?pn=118661

Choosing to go the external route works, and is a hell of a lot easier to do.

Of course it is up to you. I just tossed out a viable solution to help you along.

[ThinkPad]

Originally Posted by WeeYari

[...]
Of course it is up to you. I just tossed out a viable solution to help you along.

I understand, that is why i said "no flame intended". However, i just don't see it as a neat solution myself

In Europe when a trailerhitch is installed, most of the time the power for lights and stuff is just leeched from the rearlights. And if you need a wire from the battery (for a powered coolingbox/subwoofer/trailer) in the trunk, it is run underneath the carpet along the interior :)

I just returned from holiday and used the inverter quite often. It is so nice to have mains power (230V) available to, for example, charge my laptop, DSLR-battery and even my electric toothbrush No fiddling with 12V converters specific for each device, just plug it in like at home. I have a inverter with a pure sine wave, so every device is working happily with it. In the past i had a inverter with a modified square 'wave', but not all devices liked that, some chargers would make weird buzzing noises and got hotter than while used at home.