Headlights flash about once an hour?

Tiny
DAVENOOB
  • MEMBER
  • 2005 FORD FIVE HUNDRED
  • V6
  • 4WD
  • AUTOMATIC
  • 120,000 MILES
I have installed plug and play led lights on my Ford. I'm pretty sure this started before I changed the headlights. About every hour the headlights flash. Not the turn signals, brake lights or interior lights. This isn't great for the battery. I thought I pulled the headlight fuse but it still happens. The manual doesn't list a headlight fuse alone so maybe didn't get the right one. What could this be and how can I check this issue? No check engine light on.
Thursday, November 20th, 2025 AT 11:42 AM

17 Replies

Tiny
KEN L
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Yep, I would look for melted connector at the fuse #19 which is in the fuse panel under the hood and can cause this issue. You can upload a short video or image of the fuse if you are unsure. If that look okay chances are the SJB is bad which is at the left side of the dashboard and it is very common to go bad. Here is the location so you can swap it out which should fix the problem. I will email you the SJB as well. Check out the images (below). Please let us know what happens.
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Friday, November 21st, 2025 AT 10:39 AM
Tiny
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Thanks. The thumbnail doesn't show anything. I got an email from you with sbj diagram but not the legend that tells me what the numbers are pointing to.
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Friday, November 21st, 2025 AT 1:39 PM
Tiny
DAVENOOB
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Is the sjb also the control module or keyless alarm kit? Looking for parts that keeps coming up in search.
5F9Z-15604-DA 5F9Z15604DA - Ford Parts Giant https://share.google/rzy5m1sDQ1UqraHYc
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Friday, November 21st, 2025 AT 3:40 PM
Tiny
KEN L
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Yep, and yep, that is the part you need, to help confirm the issue you might want to do a CAN scan, this video will show you how.

CAN SCAN - https://youtu.be/u-4syLc-ifQ

Let us know how it goes.
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Saturday, November 22nd, 2025 AT 9:24 AM
Tiny
DAVENOOB
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Thanks. On the YouTube video description there is a link to a CAN scan tool pretty cheap but only works on 2006 an newer. My ford is a pre March 05, yes this makes a difference sometimes. Is there a CAN scan tool that you would recommend that would work for my 05 Ford and 13' impala?
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Saturday, November 22nd, 2025 AT 10:10 AM
Tiny
DAVENOOB
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The diagram you sent doesn't have any labels. I don't know what I'm looking for on the sjb. Here is a video of sjb and pics of fuse.
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Saturday, November 22nd, 2025 AT 7:49 PM
Tiny
DAVENOOB
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Here's the video
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Saturday, November 22nd, 2025 AT 7:51 PM
Tiny
KEN L
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The image of the fuse is hard to tell what is it is good or not so I would try a new fuse or test that one with a volt meter set to continuity. Yep, that is the BCM - SJB here is a scanner that will work for your 2005 car.

https://amzn.to/3LXAVq6

Lets see if there are any codes. Let me know ;)
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Sunday, November 23rd, 2025 AT 10:40 AM
Tiny
DAVENOOB
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The fuse is intact with no corrosion on tabs or insert. The sjb I have issues with. How do I get those big wiring harnesses off? I unlocked the catch but not sure if I can wiggly it out or pry it out? Where am I supposed to be looking for damage? I can't see anywhere around the box. Do I need to remove the box to see properly? If so do yiu have a video? I have no clue when it comes to electrical. Thanks again. Will run continuity test on fuse. Now if I run a continuity test where the fuse goes should it beep or have any voltage readings? Will that help diagnose?
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Sunday, November 23rd, 2025 AT 3:29 PM
Tiny
DAVENOOB
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Fuse past the continuity test. I put multimeter to the tabs where the fuse goes and it read 12.38v with the engine and lights off. I tested other fuse spots and they had no voltage draw. I don't know what that means but does this help or prove anything?
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Sunday, November 23rd, 2025 AT 3:35 PM
Tiny
KEN L
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Yep, if the fuse past the test I would get a SJB, search for one that preprogrammed on ebay or google. The electrical connector should be straight forward, release the safety and pull straight off. This should fix the problem.
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Monday, November 24th, 2025 AT 9:36 AM
Tiny
DAVENOOB
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I pulled this sjb off the exact same car but numbers seem different. Will this one work?
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Sunday, December 14th, 2025 AT 4:58 PM
Tiny
KEN L
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It might, if the connectors plug in I would give it a try. Let me know please. Ken
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Monday, December 15th, 2025 AT 11:58 AM
Tiny
DAVENOOB
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Thanks. Since it's used it should be programmed already right?
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Monday, December 15th, 2025 AT 2:52 PM
Tiny
KEN L
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I think the SJB is plug and play, I would give it a try to see what happens.
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Tuesday, December 16th, 2025 AT 9:55 AM
Tiny
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Will let you know thanks
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Tuesday, December 16th, 2025 AT 11:34 AM
Tiny
KEN L
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Sounds good
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Wednesday, December 17th, 2025 AT 9:01 AM

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