[seanrm92]

Hello all,

I recently acquired a set of OEM ST3 headlights for my 2014 ST1. I plugged them in just fine, and used Focccus to update the BCM for "HID" headlights and "LED DRLs". They now function properly with the exception of the turning lights (as expected, since the ST1 doesn't have that functionality).

However, now when I turn the car on I get a warning saying "Headlight fault, service required". I've seen other people mention this issue, but haven't seen any discussion on how to solve it. So has anyone been able to resolve this warning? Is it a setting in the BCM that I need to update with Focccus/Forscan or do I need to modify the wiring at all? Or maybe just "cheat" and turn the warning off (without affecting other warnings, obviously)?

I intend to do a write-up on this if I get it done since there's really not much information out there for a direct OEM swap like this.

 

[JCH841]

How old is your battery/what is its condition? My ST3 started throwing this code when the OEM battery was about 6 years old. A new battery and it went away.

 

[seanrm92]

How old is your battery/what is its condition? My ST3 started throwing this code when the OEM battery was about 6 years old. A new battery and it went away.

I think my battery is about a year or so old, it shouldn't be the problem. The warning message was a direct result of putting the ST3 headlights into my ST1, and then setting the BCM options to HID+LED DRL which as far as I know is the only way for them to function properly. I tried "Alternative HID" but the headlights would start flickering. Same if I left it on the default "halogen" option.

Edit: Also, I did NOT get the headlight warning message when the BCM was set to those other modes. They just didn't function properly.

 

[ddfred]

I think my battery is about a year or so old, it shouldn't be the problem. The warning message was a direct result of putting the ST3 headlights into my ST1, and then setting the BCM options to HID+LED DRL which as far as I know is the only way for them to function properly. I tried "Alternative HID" but the headlights would start flickering. Same if I left it on the default "halogen" option.

Was the battery life monitor reset when the battery was installed? If not, the battery may be on it's way out. The computer won't allow the alternator to charge it propoerly if the system was not reset.

 

[seanrm92]

Was the battery life monitor reset when the battery was installed? If not, the battery may be on it's way out. The computer won't allow the alternator to charge it propoerly if the system was not reset.

Considering I only got this warning after swapping the headlights, and other people have reported the same issue after swapping the headlights, I really don't think it's the battery unless someone has an explanation why. Since my battery is relatively new I'm not planning on replacing it anytime soon. (When I eventually do, if the warning goes away because of it I'll let you know lol.)

I started the car multiple times after the headlight installation without issue.

 

[seanrm92]

Something else I meant to mention in my original post: The ST3 headlights have two extra connector pins relative to the ST1. I'm not sure if the car-side connector on my ST1 has these additional connections. I suspect this is related to the problem, but I don't know what to do about it. See below for pictures.

Edit: As shown in a later reply, the numbers here are NOT the same as the wiring diagram.

 

[Dustin02]

Seems like you should have more pins than that...

Headlight plug wiring diagram

Does anyone have the headlight wiring diagram for a 2017 ST? I’m trying to figure out which color wire is the turn signal in the plug that connects to the headlight. Any help is greatly appreciated!

www.focusst.org

 

[seanrm92]

Seems like you should have more pins than that...

Headlight plug wiring diagram

Does anyone have the headlight wiring diagram for a 2017 ST? I’m trying to figure out which color wire is the turn signal in the plug that connects to the headlight. Any help is greatly appreciated!

www.focusst.org

That thread is for a 2017. Is the wiring the same as 2014? The connector certainly looks different.

 

[Dustin02]

Hell if I know... try to find one for your year and compare.

 

[seanrm92]

Okay turns out they ARE the same. Cool. Found the connector diagram. (The diagram has a slightly different shape than the real part which is why I initially thought they were different.)

The two primary extra pins are pins 6 and 9 for the cornering light and an additional ground. This is where my experience wears thin, because I am not electrically inclined (I can do some basic soldering and that's it). So do we think I need to ground these connectors? If so, how?

There's also connector 13, for a "fuse output or circuit breaker". The ST3 headlight doesn't appear to have a connector here so I'm not sure if it's necessary?

 

[seanrm92]

Update: Did some more digging today. Experimented with FOCCCUS settings and reading the fault codes in Forscan. I think I'm closer to identifying the problem, if not the solution.

First, I checked the headlight connector again and sure enough, the car-side connector has all 8 connections from the diagram in the post above. So plugging them into the ST3 lights makes all the connections EXCEPT for pin 13 (circled blue), which does not have a corresponding pin on the headlight side as shown in my previous post.

Then I went into Forscan to read the error codes, but first it's important to note what I had selected in FOCCCUS. For #14 headlight type, I had "HID", and for #16 DRL I had initially selected "LED DRL" - assuming that's what was needed.

(Note in this pic "Without DRL" is highlighted, but I had "LED DRL" selected initially.

With "LED DRL" selected, the fault code is "Left/Right Daytime Running Light - Circuit Short To Battery Or Open". So I figured that the DRL option was related to the issue. I changed it to "Without DRL (standard light)" and then "Unknown". With either of those options, the fault code was now "Lost Communication with Headlamp Leveling Control Module".

Left: Fault code with "LED DRL". Right: Fault code with "Without DRL (standard light)" or "Unknown".

So here's my conjecture based completely on my gut and could be totally wrong:

With FOCCCUS #16 set to "LED DRL", I think that power is being sent to pin 13 which doesn't have a connection, causing the fault code. I think this could potentially be solved with some sort of wiring solution, but I'm not smart enough with electronics to know.

Then with #16 set to an alternative option, the DRL is no longer the issue and instead the problem is that the BCM is looking for a headlamp leveling control module which my car does not have. From what I've read, this wasn't installed on Focuses in the NA market, but the FOCCCUS software is Russian (I believe). So they may have written the "HID" option in #14 specifically for headlights equipped with this leveling module. As I noted earlier, changing #14 to "alternative HID" causes flickering and headlight failure upon starting the car, but it does NOT display the "Headlight fault" message. Perhaps there's a way to solve that flickering problem outside of FOCCCUS. Or it's just plain incompatibility. I don't know.

Thoughts?

 

[seanrm92]

Update on this. Haven't had much time to work on it the past few weeks since I've been busy. I seem to be at an impasse. I thought I could use Forscan to go into the more detailed BCM page to maybe find a way to turn off the headlamp leveling control module to stop it from looking for it (I'm not even sure if that's an available option), but Forscan will not let me access it. When I try to go into it I just get an error. I thought it was an issue with the cable, so I bought the upgraded "OBDLink EX FORScan OBD Adapter", but no dice. I think it might be a Ford security issue or something. If anyone has any insight it would be appreciated, but otherwise it seems like I'm just stuck with the fault code every time I start the vehicle. Luckily the headlights are such a good upgrade from the ST1s that I'm fine with living with it.

 

[seanrm92]

How old is your battery/what is its condition? My ST3 started throwing this code when the OEM battery was about 6 years old. A new battery and it went away.

Update: I just swapped the battery. The "headlamp fault" message remains. So the issue is not the battery.