12v electrical wiring advise/help needed.

[binge]

Hope this is in the right section... It is pretty geeky.

I fitted some leather seats in the Pajero over the last couple of days.
They came out of an 05 Renault Laguna.
They are heated, and fully electric (moving back and forward, up and down etc).

I fitted the passenger one first (for obvious reasons), and it all went in fairly well.
The plug to fix it into the car loom was quite simple. With a couple of wires for the airbag, and pretensioner. Leaving only 3 more wires. 1 being a common earth, and the other two for the power to the seat motors, and the heating pads.

All switches are built onto the seat, for motors, and heating.



So today, I go to fit the drivers seat.
Flip it over, and find a great big ECU type module bolted to the bottom of it, and about (No joke) 40 wires, coming in and out of this thing!
Upon closer inspection, it seems like it must relate to the cars ECU (in the Laguna) and does that memory/convenience thing when you take the keys out, and put them in.


So I started snipping the loom away, to find these 3 wires (red, yellow and black)...

Yeah, they don't exist on the drivers side.

So I've stripped it back to very basics.

2 wires to each motor (3 motors, so 6 wires in total).

(The heating I can manage)


So when you blast a live and earth to these wires to each motor, they move one way.
When you reverse the polarity, they move the other way.

Simple stuff right...?



So now I go about working out the switch panel, to buddy them up with their corresponding motors.

The switch panel, has 9 wires coming out of it.

I've managed to work it it out, so that when I get two of the wires (both black wires), and give them a earth and a live.
Using a power probe/multi meter, when I switch each switch on the panel, one of the other wires will give a live feed.
But when I switch the switches the opposite way, that same wire, will then give an earth feed.

I can only get 3 of the 7 remaining wires to do something, all the others seem dud.

And those 3 remaining wires, will either go live, or earth, depending on which way I flip each switch, to tilt the seat either forwards, or backwards.


How can I then translate that feed, from a single wire, over to the motors to make them do their thing?

Or am I stuffed?




Another option was to just do away with the switch panel, and buy 3 aftermarket switches to fit into the centre console or something...

But can switches like this be bought? So that when flicked one way, they give out an earth and a live.
Then when flicked the other way, the give out a live and an earth (opposite polarity).



Any help MUCH appreciated, as my brain is hurting!


https://scontent-lhr3-1.xx.fbcdn.net/hphotos-xfp1/v/t1.0-9/12002757_10154166195225606_1186635650794437115_n.jpg?oh=6f890177c4367847856bea5b629fb875&oe=56616352

[WD Forte]

But can switches like this be bought? So that when flicked one way, they give out an earth and a live.
Then when flicked the other way, the give out a live and an earth (opposite polarity).

Yes easily with a centre off 6 terminal rocker switch
for seat positioning I'd use a momentary type like this

https://www.ebay.co.uk/itm/Momentary-Latching-6-Pins-2-Circuits-Rocker-Switch-16A-250VAC-colour-BLACK-/170927965223

Check you get the On Off On momentary type not latching

Supply and ground to centre pins and power out to each pair of output pins inverted/crossed over.
____________________
bikers smell of wee

[binge]

Just a thought....

Would electric window switches be any good?
Like, a panel out of a car which has 4 switches on it. Could be quite easily modified to fit into the side of the seat.

[WD Forte]

They may well be.
Just had another look at your pic and the exisiting ones may be used
but it depends on what type they are
Generally speaking, when I'm mixing matching stuff from one
system to another I like to have diagrams for both if possible and 'map' out switch functions.
All you need is a meter and notepad and test/jot down what they do in any position.
this will tell you how they can/can't be configured.

Looking at them I'm guessing the front is a seat temp control
the horizontal one is forward back and the vertical one back angle?
More guessing but i'd expect the front to be some kind of potentiometer and the other two to be lever type switches.

I'd examine them first to see what they actually do as it would be nice and neat to use them instead of patching in others
____________________
bikers smell of wee

[binge]

The single button right at the front of the seat is indeed for heated seats. I can manage that one easily on both seats.
The function panel on the side of the seat has the 2 shuffle switches.
The back rest one, is simply forwards and backwards, it will tilt the back of the seat.

But the base one, is a 4-way switch, it moves forward, backwards, up, and down.

I've ran a multi-meter and a power probe through the wires and mapped them out. But it doesn't seem to give out any real clues.

Giving 2 of the main feed wires a current (Live and earth).
Each button will only signal 1 wire. And only 3 of the wires will signal.

The way it works is, when you push a button one way (For arguments sake, the back rest), it will give 1 single wire, a 12v output.
When you push that same button the opposite direction, it will give that same single wire, an earth.
When you let go, it becomes a dead wire/open circuit.

There is no earth/live combo out of any 2 wires. Simply an earth, OR a live, from one single wire for each of the 3 switches.



Strange.

I assume it's like this because that live/earth output from that single wire, then instructs the original ECU on the car to do it's thing...

[sickpup]

[WD Forte]

Ok just had white board moment and this I hope is a summary
Switch (left) has 3 outputs
live, ground or no connection
Motor (right) will run in a direction dependant on supply polarity
whether its back-forward, up-down or tilt

Control is need to translate the switch output to movement and
can be done in various ways
via relays as Sickpup says or solid state devices, even a micro controller if you want but
It doesn't have to have an ECU in the sense of some kind computer
just some logic and power switching

all sorts of approaches to come to mind so I'd be mulling it over
with view to devising the simplest most reliable method

https://oi62.tinypic.com/123ryxf.jpg
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bikers smell of wee

[WD Forte]

Upon further reflection and without getting in to H bridge controllers and stuff
which is a bit overkill for a seldom used seat adjuster IMO
I'd probably build a module using 2x DPDT non latching pcb relays per motor
like this depending on load and rating.

https://www.ebay.co.uk/itm/Subminiature-12V-Changeover-Relay-2A-DPDT-/252048083292?hash=item3aaf3c895c

and configure it something like below.
You could knock it up on veroboard and the whole 3 motor controller would be fairly compact in size I reckon.
https://oi60.tinypic.com/2ura1iw.jpg
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bikers smell of wee