Driver Side Headlight Won't Turn Off

[davegrohlpike]

I have a 2018 Explorer XLT. The driver side low beam will not turn off after the car is turned off, although it will finally turn off after about 10 mins. I'm assuming there is some sort of electrical relaying telling the computer there are systems still running and they need to be shut off.

After some time (months), this issue lead to the battery dying. At that point I took it to Ford to diagnose. I was told the ballast (lighting control module) was bad and the headlight assembly would need to be replaced. I decided I didn't want to pay the labor so I did the work myself using the Ford OEM parts for both components.

The problem is still not resolved. The driver side headlight still stays on for 10 minutes after shutting the vehicle off. Does the computer need to be reset so it recognizes the parts before they will work properly?

Also, upon further inspection I found something interesting. I decided to take a look at the passenger side to see if there were any differences. The passenger side wiring harness that connects to the back of the headlamp assembly has 10 total wires, 3 to the running light and 7 to the rest of the assembly . The driver side however, only has 9 wires, 3 to the running light and only 6 to the rest of the assembly. Is this by design or is it possible that the explorer left the factory missing a wire to the driver side headlamp assembly? If so, would that explain the headlamp staying on. (Missing wire carries signal back to the computer?) I've attached a picture of each side connector (trying) to show the difference.

This forum seems to have a ton of good information so I hoping to find some help here.

 

[Michael Blackburn]

The right side Headlamp assy has 10 wires, the left 9. The extra wire is "address" and tied into the low beam.
The headlights are activated by the BCM (Body Control Module). Power comes from Fuses F48 and F50 in the battery junction box..

It is a very simple circuit. Power from the fuses goes into the BCM. FETs inside the BCM turn on to send power to the lightbulb. BCM is controlled from various inputs (autolamps, wipers, the headlight switch)

Your dealer was FOS if they said the headlight itself was the problem. BCM would be my guess.

Fritz

 

[peterk9]

Welcome to the Forum Dave.
The Battery Saver Program turns OFF all circuits that are left ON after 10 minutes except for the parking lamps. That is why the headlamp turns OFF when it does. I'm guessing that the vehicle is no longer under warranty? Good luck and please report back. Thanks.

Peter

 

[davegrohlpike]

Fritz,

Excellent information. Thanks. Couple follow ups. Can you send picture for the LH? The LH side wiring looks to be different colors.

Where is the BCM located on the 18's? Is the BCM part #14F042 or #15604? From my online searches #15604 is the fuse box/panel under the steering column. That doesn't seem right.

Apart from replacing the BCM, is there any work around to getting the light to turn off using the headlight switch? An intermediate switch perhaps?

I'm a pretty new to electrical wiring in a car so apologies for the novice questions.

Peter,

Warranty expired 3000 miles ago. I was so close. Will update and probably ask more questions .

 

[Michael Blackburn]

BCM is behind/part of the interior fusepanel. (IDK, never looked at it) Left side underneath dash.

 

[JWKberlin]

Your dealer was FOS if they said the headlight itself was the problem. BCM would be my guess.

I totally agree, the anomaly you see, is certainly related to "logic-level" and the headlight is purely analogue.
As I am foreigner - what does FOS means?

As per my 2011 owners manual there is some configuration to leave HL on after removing key, but this should be a max of 3 min - not 10 min. From my perspective it is questionable that in the digital block designers kept room for such a "delay" of 10 mins, when only 3 mins are foreseen.

Does anyone know, whether there is a safe way to reset BCM, just to check whether that solves the issue?

kind regards,
Janosch

 

[Michael Blackburn]

Yes, the lights out delay can be set in the left instrument display.
The 10 minutes comes from the "Emergency Shutoff" that kills all lights to prevent the battery from draining.
and FOS means full of human excrement.

Fritz

 

[JWKberlin]

Thank you Fritz, for the explanation - never stop learning.

Apart from replacing the BCM, is there any work around to getting the light to turn off using the headlight switch? An intermediate switch perhaps?

Wouldn't be the obvious workaround to switch it on/off manually as one used to, 20 to 30 years ago? Or is the 2018 missing that switch?

 

[JeffsNuts]

you see the corrosion around that yellow wire at the connector in your picture? the wire is broken inside the insulation....if you take a pick and pull gently on that wire it will come right apart.....that wire as an open circuit will cause a single headlight to remain in the on position for 10 minutes after the car is shut off

 

[peterk9]

you see the corrosion around that yellow wire at the connector in your picture? the wire is broken inside the insulation....if you take a pick and pull gently on that wire it will come right apart.....that wire as an open circuit will cause a single headlight to remain in the on position for 10 minutes after the car is shut off

Welcome to the Forum Jeff.
That member was last seen here on December 3, 2020, so may not be following the thread any longer. This happens way too often when a mentioned follow-up doesn't happen.

Peter

 

[davegrohlpike]

you see the corrosion around that yellow wire at the connector in your picture? the wire is broken inside the insulation....if you take a pick and pull gently on that wire it will come right apart.....that wire as an open circuit will cause a single headlight to remain in the on position for 10 minutes after the car is shut off

That was indeed the issue. Thanks for the reply Jeff.

 

[peterk9]

That was indeed the issue. Thanks for the reply Jeff.

Thanks for the reply.

Peter

 

[JeffsNuts]

That was indeed the issue. Thanks for the reply Jeff.

Thanks for posting that nice clear picture to start out with.....I had one that was stumping me and the Identifix wiring diagrams weren't giving me any obvious clues, but when I did a google search, I ended up here in this forum.....I saw that corrosion in your top pic and it lead me straight to the problem with the car I was working on.

 

[Rick Ohio]

Thanks for posting that nice clear picture to start out with.....I had one that was stumping me and the Identifix wiring diagrams weren't giving me any obvious clues, but when I did a google search, I ended up here in this forum.....I saw that corrosion in your top pic and it lead me straight to the problem with the car I was working on.

this is unreal!!!! I have this same problem with my 2018 Explorer Limited and the dealer diagnosed it telling me I needed a new headlight assembly and the total would be $1500+ with labor. I paid them the $275 they charged me for the diagnostic labor cost and took it home to do it myself. After swapping out the headlight module and swapping the drivers headlight assembly neither fixed the problem..... and now I see this post!!! Tomorrow morning I will check for a broken wire in the drivers side plug and hopefully find it and that solves the problem!!!! Thanks to you all!!

Now can anyone tell me if I have any recourse in getting a refund from the Ford dealer because again they were FOS?

 

[Mbrooks420]

this is unreal!!!! I have this same problem with my 2018 Explorer Limited and the dealer diagnosed it telling me I needed a new headlight assembly and the total would be $1500+ with labor. I paid them the $275 they charged me for the diagnostic labor cost and took it home to do it myself. After swapping out the headlight module and swapping the drivers headlight assembly neither fixed the problem..... and now I see this post!!! Tomorrow morning I will check for a broken wire in the drivers side plug and hopefully find it and that solves the problem!!!! Thanks to you all!!

Now can anyone tell me if I have any recourse in getting a refund from the Ford dealer because again they were FOS?

I don’t think so. Don’t go to the dealer unless it’s a warranty claim. Most are nothing but part swappers, and love nothing more than going whole hog. They replace everything and if that doesn’t work they feed you some BS about never seeing this before, and they’ll get engineering involved.

 

[peterk9]

this is unreal!!!! I have this same problem with my 2018 Explorer Limited and the dealer diagnosed it telling me I needed a new headlight assembly and the total would be $1500+ with labor. I paid them the $275 they charged me for the diagnostic labor cost and took it home to do it myself. After swapping out the headlight module and swapping the drivers headlight assembly neither fixed the problem..... and now I see this post!!! Tomorrow morning I will check for a broken wire in the drivers side plug and hopefully find it and that solves the problem!!!! Thanks to you all!!

Now can anyone tell me if I have any recourse in getting a refund from the Ford dealer because again they were FOS?

Welcome to the Forum Rick.
I also doubt that you have any recourse in that they did perform the diagnostics and no parts were replaced. In other words, you paid for a service and received it. Please report back with your findings. Thanks.

Peter

 

[Mbrooks420]

That said $275 for diagnostics is spendy.

 

[kerrybrod]

So i have the same headlight issue on my 2017 FPIU but my wires on the plugs look like new and clean. should I check the bcm fuses or just get a ballast ???

 

[Tristan Smith]

So i have the same headlight issue on my 2017 FPIU but my wires on the plugs look like new and clean. should I check the bcm fuses or just get a ballast ???

I have exact same issue with my 2017 fpiu as well. What did you end up doing?

 

[Dustin86]

That was indeed the issue. Thanks for the reply Jeff.

Hey guys,
I have the exact same issue with the corroded wire on the module. HOW do you fix the one wire? Do I just pull out of the plug a bit and remove bad part of wire and stick back in? Not a mechanic so apologize for my ignance