Heated windshield retrofit finally done!!!

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Aug 19, 2021
Hi. I'm from europe and we have cold winters. Heater uses a lot of energy and i only need clear windshield.

Edit: See last post how it was done.

So I'm going to retrofit instaclear ford windshield. Maybe there is someone who knows more information for electric part. I saw ICE focuses retrofits. They use fuse 14,16 and relay 7 or 15. In our focus there are no space left for heated windshield relay and fuses. I'm going to fit them in some other place. Only thing that is unclear for me is output from BCM (body control module). I activated heated windshield with forscan, bcm says that i have no relay. So i will try searching for it. Wish me luck. I will update post when i do some progress.
I'm going to guess that the connections that would go from the BdyCM harness to the fuse/relay block don't exist, assuming they didn't get reused for something else. So you may have to tap to the module itself. May still work.

Do you have the wiring data for the electric? What year is this on?
There was no wires to bcm (no for button, indicator or relay). The relay works when i press max defrost on hvac. But the button i wired to bcm does nothing.(does not turn on relay, no indication) My 12v battery is 58% charged, hope it's battery fault. All space in relay block is used (for some ptc heaters, maybe hv battery heaters). I will have to place my relay and fuses outside of it.

I have 2014 wiring diagrams of electric. It does not mention anything about heated windshield. For windshield part i use some 2011 ICE focus schematics i found online. My car is 2014, still going. :D
I'm skipping the programing part, couse i had no luck with forscan or focccus apps. Our focus has a bit different layout of modules. (Like 12v battery management is in BdyCM, becouse BECM is for high voltage battery).

I made simple timer box with oem relay and fuses, and i will use original button. Windshield still did not arrive, so i have time for preparations.
I finally done the heated windshield modification. Of course pity that I had to wire my own system instead of using ford's oem windshield control. But everything works as intended and overall i am satisfied. In cabin everything looks an feels like oem. (Button, negative connetion wires). It draws around 750 watts (51A) from 12v system, and effect to range is minimal.

Here's couple pictures of what i done:

Here we can see how foggy side of windshield is compared to heated area. Elements defog screen very fast.

My homemade control box. Timer, power and two control relays. 2x40A fuses

Box installed in car

Found spare space and installed 60A fuse. Hadn't blown yet.

Very sketchy roof negative pole connections.

The thing where everything is being installed
Nice. There is a thread from long ago with a command that would kill the heater cycle. Between the heated seat and defrosting, that might be worth setting up.

Luckily mine focus is imported from USA and has all the controls (e.g. go times for preheating), and when I have heated windshield, I don't use blower at all. Heated seat + warm glowes + heated screen = maximum possible range. :D