Heated seat wiring help (aftermarket kit)

[Dino D]

So I'm replacing my OEM heated seats with Sparco seat and fitting aftermarket heated seat pads to the Sparcos. So the car already has working OEM heated seat switches and relay and wiring. I am looking to use the OEM switches and not the switches that come with the seat pads. The seat pads are 2 stage heated like the OEM.

I need some help from those who have done this ( I think @Sean d and @Antm72 have done this) as to what wires to connect to what.

OEM wiring and plug under seat 4 wires 2 brown and white/yellow +white/black

OEM switch with 6 wires?

Heated seat pad (2 parts back rest + seat base which connect to one plug)
This has 4 wires (2 green and 2 red/white)

I was planning to use the connector that comes with the kits and cut it and join it to the in car loom so that I have plug. However it has 4 wires: red/white, purple, green, black.
So which do I connect to the cars loom which is 2 brown and white/yellow +white/black?

 

[Antm72]

I think the 4 wire plug is just the 2 pairs that feed each pad.
As I only retro fitted the pad I only dealt with the pad and the two wires and the original pad is also just 2 wire so it was just a like for like swap. You may be able to find the info in the wiring diagrams, they are on here in the resources section I think .
The six wires will include the lighting to the switch etc the diagrams should help identify them

 

[Stevo7682]

Dont know if this any help

this from my haynes 3 series / z3 manual

161 is the switch
Going on that the white / yellow and white / blue are the 2 seat lives
The brown goes to earth
Brown / red dash illum
2 red/ yellow to 160 underloader relay


163 and 164 are the seat heaters
So on your 4 pin plug the 2 brown both earth other 2 lives for base and back pads

 

[Dino D]

So on your 4 pin plug the 2 brown both earth other 2 lives for base and back pads

This helps thanks. The OEM plug from the car side is straightforward then.

I want to cut and join the connector below to the car side. But anyone know which of these 4 on the aftermarket plug are are earth?
black one must be so leaves one other choice- green/white, red/white or purple?

 

[Stevo7682]

This helps thanks. The OEM plug from the car side is straightforward then.

I want to cut and join the connector below to the car side. But anyone know which of these 4 on the aftermarket plug are are earth?
black one must be so leaves one other choice- green/white, red/white or purple?
View attachment 62705

Whats at the other end of that cable

 

[Stevo7682]

Been thinking are you not over complicating matters .
Why do you not connect the red / green wires from the pads straight to the cars original 4 pin plug and use oem wiring from there do away with the rest .

 

[Dino D]

Been thinking are you not over complicating matters .
Why do you not connect the red / green wires from the pads straight to the cars original 4 pin plug and use oem wiring from there do away with the rest .

Yes you right.
The only wiring that I use from the kit is the 4 green and red wires from the pads themselves. I'm assuming the red are live and green are earth?

As I want this to be easily unplugged when removing seats I just need to use the corresponding connector from the kit to replace this black plug from the car:...

...with this plug here, the colours on this plug are really irrelevant as they will be joined with the brown and white wires from the car:

So am I right in thinking the the red wires on the kit are live and the green are earth so that I connect up properly:
Greens to browns?
Reds to whites?

 

[Stevo7682]

If the two green are just green they will be earth. 1 red solid and 1 red white trace i take it .
If so 1 red from base heater the other from back should be eay enough