I have a Ford Focus Mk3 (registered in February 2013) without automatic headlights.
I recently bought it as a used car.

Everything was working fine until I recently replaced the headlight bulbs, and then a strange issue started occurring.

The problem is that even when the headlight switch is set to OFF, the headlights automatically turn on and stay on when I turn the ignition key to the ACC position.

Before replacing the bulbs, the headlights would not turn on in the ACC position if the headlight switch was set to OFF — which is the expected behavior.

What could be the cause of this issue, and how can I fix it?

what happens when you turn the headlights to ON  ??

By any chance, did you replace the bulbs with LED ones?

5 hours ago, FocusMk3User said:

Before replacing the bulbs, the headlights would not turn on in the ACC position if the headlight switch was set to OFF — which is the expected behavior.

Put the old (correct) bulbs back in the headlights.

Thank you all for your replies.

Since I didn’t fully understand the issue, I’d like to explain again.

I replaced the standard halogen bulbs with LED bulbs.

At that time, I did get an error message, and when I turned the headlight switch to the ON position, the lights would turn on briefly and then turn off. However, after trying several times, although the error message still appeared, the headlights stayed on once switched to ON and no longer turned off.

After that, I also had the turn signals replaced with LEDs. That’s when the turn signals started acting strangely.

Later, I had my mechanic take the car to Ford to see if they could fix the issue of the “headlight bulb failure” warning. (I didn’t go myself—I left the car with my usual mechanic, who took it to a Ford contact he knows.)

I had seen online that if you go into the submenu under #14 Headlights and set it to “ignore bulb check,” the error message would go away.

However, when Ford checked, they confirmed that while there is a #14 Headlight menu, there was no selectable submenu under it. So, they connected the diagnostic terminal to check, but they told me they didn’t change anything.

After the car came back, the side windows began acting strangely. When I asked another mechanic about this, they said, “That’s probably because the power was disconnected. It should fix itself soon.” And indeed, shortly after, the side windows returned to moving smoothly.

However, after the visit to Ford and the diagnostic check, the headlights started acting up again.

It’s normal to see the error message, but now, when I turn the headlights ON, they briefly light up and then turn off again.

Also, from this point on, a new issue started: even when the headlight switch is in the OFF position, if the engine key is turned to ACC, the low-beam headlights automatically turn on. In other words, when in ACC mode, the low beams and position lights come on—even if the switch is OFF—and I can’t switch to high beams. Only the low beams come on. And when I turn the headlight switch to ON, the headlights light up briefly and then turn off.

Because of all this, I did some research and visited a shop that sells LED kits specifically for the Ford Focus. They replaced the LED kit with one that works properly without any issues.

(During this, the previously installed LED bulbs were removed. All the LEDs—including the turn signals and rear brake lights—were removed, and only the shop’s Ford Focus-specific LED kit was installed.)

The shop told me that they’ve installed countless Ford Focus LED kits before, but they’ve never seen symptoms like the ones my car is experiencing.

(The kit is designed to comply with vehicle inspection standards, so I’ll refrain from discussing the quality of the LED kit itself.)

As things stand now:

Even if the headlight switch is in the OFF position, turning the engine key to ACC automatically turns on the low beams. That is, even in OFF, switching to ACC causes the low beams and position lights to turn on. However, I still can’t switch to high beams at this stage. When I turn the switch to ON, the headlights turn on normally and stay on. I can switch to high beams without any issue, and the headlights work as expected when used this way.

For normal use, having the low beams turn on automatically with engine start doesn’t pose a driving issue—but ideally, I’d like the headlights to stay off when the switch is in the OFF position, as they did before.

ChatGPT suggested that it might be a faulty relay.

Has anyone else experienced or repaired similar symptoms?

1 hour ago, FocusMk3User said:

ChatGPT suggested that it might be a faulty relay.

🤣🤣🤣🤣😂😂😂😂🤣🤣🤣🤣

56 minutes ago, FocusMk3User said:

I replaced the standard halogen bulbs with LED bulbs.

fault is right there...

17 minutes ago, unofix said:

🤣🤣🤣🤣🤣🤣🤣😂😂😂😂🤣🤣🤣🤣

Are you implying that AI has far in excess of 'Artificial', and nowhere near enough 'Intelligence'?? 😂

I just hope and pray that the NHS don't use Chat GPT for making diagnosis 😟

7 minutes ago, unofix said:

I just hope and pray that the NHS don't use Chat GPT for making diagnosis 😟

Labour use it for policy direction I believe.

They've just upgraded to a Sinclair Spectrum 128k

The P.M also has a VPN I presume, he'll need it now

Anyways, back to the post

The headlamp bulbs you have bought are rubbish and shorting.

You can't fit LED bulbs in halogen reflectors, they just don't work

Just buy better H7 bulbs Osrams or Philips

Also, never use LEDs in indicators, apart from the door mirror repeaters, as the system just doesn't like them.

If you want to get rid of the orange bulb fit some silvertec bulbs

39 minutes ago, DaveT70 said:

You can't fit LED bulbs in halogen reflectors, they just don't work

We'll just disagree with that. However, my car is much older than the OP so it doesn't have any fancy self checks to speak off, when I turn the headlights on, it simply supplies a 12v supply to them and my car is too dumb to know otherwise. Largely I agree with everything you say, though last week when my side indicator literally broke its casing, I replaced with LED sequential ones which work a treat!.

 

Notice: The issue has been resolved successfully

Hello everyone,

I'm writing to let you know that the issue has been successfully resolved.

At the same time, I also obtained some very useful information, so I hope this post can be helpful to others as well.

Earlier today, I personally visited the Ford dealership where the device had been connected to my car last time.
As it turns out, that visit led to the resolution of the issue.

At first, they said they “hadn’t done anything,” but as it turns out, they had—and that turned out to be the root cause.

The problem:
Even when the light switch was set to OFF, both the low beam headlights and position lamps would turn on as soon as the ignition key was turned to ON.
This turned out to be due to the ECU’s programming.

In some Nordic countries, it's legally required to have headlights on even during the day.
My Ford Focus is a model that came just before Daytime Running Lights (DRL) were standard.
However, the DRL setting was still present in my car’s ECU.

So in this case, the issue was caused by the DRL setting being enabled.

Originally, before my car was taken to Ford, the DRL setting in the ECU was disabled.
But when my mechanic took it to Ford Assistance previously, they apparently enabled the DRL setting and registered that new configuration into the ECU
(as if the system had been completely powered down and rebooted with the new setting).

As a result, the side window behavior temporarily became abnormal,
and from that point on, the low beams would automatically turn on as daytime running lights whenever the ignition key was switched to ACC—even if the light switch itself was set to OFF.

As you may know, the original Ford Focus Mk3 did not come with DRLs, either as standard or optional equipment.
Instead, it had a function where the low beams could be used as DRLs by configuring the ECU.

The DRL setting had three options:

Enable low beams (and position lamps) as DRLs

Enable only “P-lights” as DRLs (I’m not sure if this refers to Position or Parking lights)

Disable DRLs entirely

In my case, the root cause was that option 1—"Enable low beams as DRLs"—had been selected.

So I asked Ford Assistance to disable the DRL setting again and install that configuration into my car’s ECU.

As a result, when the light switch is OFF and the ignition is turned to ACC, the low beams and position lamps no longer come on.
That resolved the issue completely.

If, on the other hand, you do want your low beams to stay on during the day for safety reasons, any Ford Focus Mk3 owner can simply visit a Ford Assistance center and have the setting enabled easily.

I’m not sure about the cost, but the whole process only took about 10 minutes.

So, I just wanted to report that the issue has been fully resolved, and that I made a new and useful discovery.

Also, my LED lights, which are road-legal and passed inspection, are working perfectly without any error messages.
They’re nice and bright, and I’m very satisfied.

I hope this information is helpful to others in some way.

That’s all from me. Thank you so much!

1 hour ago, StephenFord said:

We'll just disagree with that.

They don't work though, you never get the right beam pattern. 

As I said side repeaters work, but LED indicator bulbs just cause hyperflash

1 minute ago, DaveT70 said:

They don't work though, you never get the right beam pattern.

 

Happy to accept that. Though I'm happy with the beam pattern, and they have also passed 3 consecutive MOTs and also the adjustment ensures I don't blind oncoming drivers...

P.S.

This is not the place to debate the pros and cons of LED lights or their patterns.
This forum, as I understand it, is meant to be a space for sharing knowledge to help resolve vehicle-related issues.

Irrelevant replies—especially those unrelated to the question of why the lights were turning on—only serve to confuse others.

For the record, the LED lights I installed are legal and passed vehicle inspection.(NOT UK)
In fact, I had the inspection done today, and there were no issues.

It might be a good idea to reconsider the belief that your knowledge is always absolutely correct.

With that, I’ll take my leave. Goodbye.

2 minutes ago, FocusMk3User said:

P.S.

This is not the place to debate the pros and cons of LED lights or their patterns....

With that, I’ll take my leave. Goodbye.

LOL I'm sorry - don't you understand how the internet works? 🤣

Don't slam the door on your way out...

Here in France there are legal H7 LED headlamps. They are about 130 Euros a pair and both Philips and Osram can supply them. I might consider a pair for the outer projectors.

14 minutes ago, StephenFord said:

Happy to accept that. Though I'm happy with the beam pattern, and they have also passed 3 consecutive MOTs and also the adjustment ensures I don't blind oncoming drivers...

You'll have to tell me what they are then😉

11 minutes ago, FocusMk3User said:

P.S.

This is not the place to debate the pros and cons of LED lights or their patterns.
This forum, as I understand it, is meant to be a space for sharing knowledge to help resolve vehicle-related issues.

Irrelevant replies—especially those unrelated to the question of why the lights were turning on—only serve to confuse others.

For the record, the LED lights I installed are legal and passed vehicle inspection.(NOT UK)
In fact, I had the inspection done today, and there were no issues.

It might be a good idea to reconsider the belief that your knowledge is always absolutely correct.

With that, I’ll take my leave. Goodbye.

Blimey, there's some touchy people lately.

I'm starting to think it's probably easier to not bother commenting at all.

Yeah, see you👋

1 minute ago, DaveT70 said:

You'll have to tell me what they are then😉

Have a look at my last post - i re posted the whole original 'LED' bulb post I did years ago LOL

Just now, StephenFord said:

Have a look at my last post - i re posted the whole original 'LED' bulb post I did years ago LOL

Thanks👍