Retrofit Auto Lights on a 2017 Ford Focus

Recommended Posts


I'm looking at retro fitting auto lights to my 2017 Focus St-Line MK 3.5

I've purchased the switch which includes the auto feature. When I set the switch to the auto setting, the lights stay on in broad daylight.


I know I might have to enable the setting in the BCM, which i will need to purchase modified ELM327 unit to do this.

There's two sensors on the windscreen and one in the middle of the dash.

Windscreen Sensors

Dash Sensor

I'm not even sure if it is possible as the vehicle is fitting with Auto-Start-Stop and I've read that if the vehicle has that feature then it can't have auto lights as the sensor location is already being used.

If anyone can shed any light if this is even possible I would be very grateful.

Share this post

Link to post
Share on other sites

can't see your photos.

It may look like you have the sensor in the windscreen but it may be a blank.

Take the mirror shrouds off and have a look.

You will need to research the wiring diagrams (MK3.5 is same as MK3) and add a tiny loom down the A-Pillar down to the BCM. Check first though that the wiring isn't already there if you have active city stop etc, hiding in the head liner


Then you need to activate auto lights and auto wipers in the BCM using Forscan and a modified ELM327 cable, you also need to activate auto wipers in the IPC.

The sensor in the top of the dash is for auto dash dimming

Share this post

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.