Retrofit after market heated seats...

[JW1982]

Based on the schematics the original switch has a 2610 Ohm resistor in series with a 0 to 5000 Ohm potentiometer. If this is true the resistance circuit of the switches varies from 2610 Ohm to 7610 Ohm depending on the position of the switch.

There basically are 2 possible ways to connect the original switches to aftermarket seat heating elements that do not match the resistance/capacity of the original seat heating elements:

1. By converting the components of the original switches to match the characteristics of the aftermarket switches. Most aftermarket seat heating elements are directly controlled by the switches without a control module. When converting the components of the original switches to match the characteristics of the aftermarket switches you have to make sure that the components are capable to handle the current. 

2. By using a custom made control module. For example an Arduino based control module that detects the position of the original switch and controls the aftermarket heating elements using PWM control.

[Nathan Buffery]

4 hours ago, JW1982 said:

There basically are 2 possible ways to connect the original switches to aftermarket seat heating elements that do not match the resistance/capacity of the original seat heating elements:

I haven't got aftermarket heaters. I have upgraded my seats to ones which have heated seats. My issue is mounting the switch, because I have fitted the facelift centre console. The trouble with most of the focus' switches are they dont sit flush so it's near impossible just to drill a hole in a panel and mount them. I was considering tracking down a switch from Ali Express with the same resistance. 

[JW1982]

I see. Now I understand what you are after.

In your case you can buy any aftermarket switch you want as long as it has the same amount of positions as the original switch. You need to convert the components of the aftermarket switches to match the characteristics of the original switches. There is a 99% chance that the resistors and potentiometers of the aftermarket switches need to be changed.

[JPW]

Can't you just change your retrofitted mk3.5 climate control panel to the one that has the heated seat buttons or did you not change that with the new console?

[Nathan Buffery]

25 minutes ago, JPW said:

Can't you just change your retrofitted mk3.5 climate control panel to the one that has the heated seat buttons or did you not change that with the new console?

Mate, I spent months trying to get the facelift climate module to work in my focus. I had the basic twisty knobs and I studied the wiring diagrams and swapped all the pins over. But it never worked properly. I think I would of have to rip out the whole dash and change the blower and all the vent control system. Also, the better climate control is linked into the CamBus and is a module, whereas my wasnt really a module. I also updated the BCM to the latest, but my BCM wouldn't take the newer updates.

[JPW]

Man, that sounds like a real pain. I guess in models where the dual climate control didn't exist from factory, it's quite a big rewire and other component changes to get it working 😒

[Nathan Buffery]

This is what I ended up with as a compromise. 

[JPW]

Ah I see - nice handy work there!

 

[Dojj]

On 2/14/2021 at 8:21 AM, JW1982 said:

For heated seats you do indeed need Pin numbers 9, 10 and 17 at both seat connectors.

Below some pictures of my 2013 Focus MK3 with factory fitted heated seats:

Driver side.

 

Passenger side.

 

Note that since my car is a LHD vehicle The pictures will be mirrored on your car. The connectors and Pin numbers however are identical.

The seat side of the seat connector contains a number of color codes 2-pin connectors. The function of the connector can be identified by the color of the connector. Blue and Green are used for heated seats. Each color has a different locating tab and only fits in one position of the main connector. The seat connector is more or less standardized. The same color coding and connector pinout has been used on most Ford models for over 20 Years.

Also be aware that the heated seats require the extra fuse box in the boot. The extra fuse box in the boot is only present on vehicles that have functionality/options that require the extra fuse box. Lower spec vehicles that do not have functionality/options that require the extra fuse box do not have the extra fuse box and have less/different wiring.

just been out to the car and finally managed to unclip the cover to see this, looks like i've already got the floor loom in there and just need to plug the seat in right?

[Dojj]

On 2/15/2021 at 10:29 PM, JPW said:

Man, that sounds like a real pain. I guess in models where the dual climate control didn't exist from factory, it's quite a big rewire and other component changes to get it working 😒

dual climate has a split heater pump set up too for each side so if you don't have climate control it's very very difficult to retro fit

[Nathan Buffery]

10 minutes ago, Dojj said:

just been out to the car and finally managed to unclip the cover to see this, looks like i've already got the floor loom in there and just need to plug the seat in right?

I've also been poking around my car today. I have the wiring to the seat but not for the switch. Looking at the diagram though, I can install some pins into 13 & 14 on connector C23A and I'll tap into the yellow on my climate panel. Fuses 34 & 35 are already there in the boot, so once I get my switches sorted I'll be nice and toasty. Dyou think I'll have to alter the settings in Forscan/ Focccus to tell the car it has heated seats?

[JPW]

I recently purchased some heated seats from a Titanium X, the cup holder switches and the loom that connects under the passenger / centre console trim. If you have the loom at the seats already which it appears you do, you'll already have the wires present at that location. Might be easier to but the loom for the heated switch and just cut off what you need?

BV6T-15K857-GHC (finis 1834267) is the loom between the passenger side connector and the switch itself.

Previous eBay listing here showing the wiring loom too: https://www.ebay.co.uk/itm/Ford-Focus-Centre-Console-Media-Wiring-Loom-USB-AUX-Heated-Seats-2011-2014-/254790418928

You do not need to program anything for the pre-facelift heated seats, it's just all done by the modules on the factory heated seats provide the wiring is done! 😁

[JPW]

Dojo, yes, the wires are present at the seat so that's good!

[Nathan Buffery]

1 hour ago, JPW said:

BV6T-15K857-GHC (finis 1834267) is the loom between the passenger side connector and the switch itself.

Yeah this loom fits into C33C. But I've checked today and the pins are not coming to connection. I think they should be in connection C23A though, so I can pick them up there. Just need to decide what switches I get now.

[JPW]

That seems odd if the wires are present at the seat end of the loom but not C33C...

[Dojj]

it appears that the mk3 with the switches in the centre  near the handbrake and the mk3.5 with the switches built in use different looms on that end, but the same on the seats

[Nathan Buffery]

8 hours ago, JPW said:

That seems odd if the wires are present at the seat end of the loom but not C33C...

I had the same situation when I fitted the parking assist.  I had all the connections for the modules in the boot, but nothing for the switches and the front bumper. 

[Nathan Buffery]

@Dojj did you get the switches? I'd be really interested in what resistance is showing on each position of the switch. I'd also like to know if the switch locates on each number if you get what I mean?

[Dojj]

On 2/18/2021 at 3:40 PM, Nathan Buffery said:

@Dojj did you get the switches? I'd be really interested in what resistance is showing on each position of the switch. I'd also like to know if the switch locates on each number if you get what I mean?

i've got the facelift so my switches are in the centre by the climate controls

when i plugged the new panel in they light up and go from 3 to 2 to 1 light so i'm assuming they work

might get out there later with a tester to see if the wiring powers up and then i'll be good to go 🙂

but i've already been on the hunt for some heated seats, now i find that they come in electric versions too and full leather rather than just half my spec creep is creeping up and up and up lol

[Nathan Buffery]

I've took a chance and ordered cmax switches. I think (hope) I can fit them into the facia panel I've put in and they are the same tolerance. I think @JW1982 said the mk3 system is the same as the mk2 Focus so I'm banking on the Cmax being the same. I've also ordered a usb hub to fill the hole which fits into the cigarette lighter hole.

[Nathan Buffery]

So I got my switches. For anyone else who Is interested I took readings of the switches. Position 0=0, 1=7.71k, 2=6.39k, 3=5.17k, 4=3.87k and 5=2.61k so they match the focus wiring diagram. Just got to fit them into my panel and wire them up now. I didn't get the connections with them so I'll have to solder direct onto the pins.

[JW1982]

Do the C-max switches also have the (in my opinion) horrible red illumination?

When I bought my car in 2014 the red illumination bothered me quite a lot so one of the 1st modifications I performed was changing the red illumination of the heated seat switches to Ice Blue.

[Nathan Buffery]

36 minutes ago, JW1982 said:

Do the C-max switches also have the (in my opinion) horrible red illumination?

Ah......I haven't checked that yet. I'll let you know. I assume you took the switches apart and soldered in the blue LED.

[JW1982]

Yes, I disassembled the switch assembly and replaced the SMD LED's on the circuit board. It is however very difficult to find the correct LED color. The Ice Blue LED's that Ford uses seem to be very rare. After I ordered several LED's I did not find one that matched the original ICE Blue color. In the end I gave up and sacrificed a Focus MK3 radio control panel that I bought at a local scrap yard. I desoldered all Ice Blue LED's from the radio control panel and used these LED's to change the color of the heated seat switch assembly.

 

I also replaced all of the yellow/orange indication lights of all other switches:

 

[Nathan Buffery]

The switches are all in now. The hardest part was getting them to fit into the panel that i made up. I spliced into the yellow input live from the heater control panel and found the outputs in connection C23A pin 12 (passenger)+ 13 (drivers). Nice warm back and bum!!