Hey guys, first thing I'll say is I will gladly make a video and put it on Youtube and link it if I can't do a good job describing it, but I wanted to try first. So when I have my headlights on, obviously the tail lights are lit up as well. When I press the brake, they of course light up brighter. When I have the headlights on, the tail light will go out after I use my blinker. The side that goes out corresponds with the side blinker I use. This happens on both sides. Even after this problem presents itself, they will still go from no light at all to full brightness if I press the brake. Once they go out, they stay out until I fix it. Turning off my lights and back on again fixes the problem, but you can see how that would get quite annoying doing this every time I have to use my blinker at night.

Any ideas are welcome. By the way, I got rear ended so I replaced the lights with aftermarket lights. The problem happened before and after, so I don't think it has to do with the lights themselves. I'm sure it's a wiring issue, but I don't know much at all about electrical stuff haha. Thanks for looking

 

Smart Junction Box acting up? Sometimes they get wet because of a bad body seam fill job at the factory. It can cause all sorts of electrical issues.

 

When you say you replaced the lights with aftermarket lights...what exactly do you mean? You replaced the bulbs, the housing, or both? Replaced with new, or you bought the replacements used? Sequential or standard tails?

The reason I ask...I have a sequential kit, and experienced a strange similar issue a little while back. My lights functioned fine in the day. At night, they would get one full sequence and then shutoff and leave the front hyper-flashing every time I used the turn signal. Lights functioned as expected otherwise, and it took me a little while to figure out what was wrong. I almost gave up and just assumed it had to be the sequential harness gone bad.

But I did a little more testing one more time before sending it in for replacement...I narrowed it down to a single bulb and realized that one of the filaments was broken. So at first glance, it appeared to be working since one filament was. But something in the car...whether it was the sequential harness or the SJB...knew the bulb wasn't right. Every other bulb I've ever burned out did not have this behavior. So it may be worth double checking that your bulbs are not the culprit.

But you mention it happens on both sides, so maybe what I mentioned is not relevant and it could be the SJB. Which would be unfortunate, as that costs much more than a few bulbs.

 

Hey guys, sorry, I haven't been at my computer in a while. But they're LED lights. There isn't a single bulb in each section, I'll link it below (I regret it because I really don't like them). They aren't sequential either.

Ok, second time editing this lol. I read a little bit, not much but some, about the smart junction box. I read something about if your passenger side leaks it can go haywire, I went out to the car and while I don't know specifically where to feel, nothing was wet. It rained yesterday at Cars and Coffee pretty much the whole way there, during, and way back (pretty depressing) so I think it should have leaked if its going to. I felt all the carpet on the passenger side front and back and nothing was wet. Good sign? Or does it make my problem that much more annoying?

My lights: http://www.cgdistribution.com/prods/...005TLEDJM.html

 

Hmmm, not great...If the problem existed before you replaced the lights, then I wouldn't expect them to be related.

The Smart Junction Box (SJB) is one of the brains of the car that controls the electronics. It's essentially a fuse box located in the passenger foot well. It's commonly damaged by water leaks in that location, and results of the electrical damage can be...unpredictable, to say the least.

 

The Smart Junction Box is behind the right passenger's side kick panel.

Is you carpet wet there? If not and the fact you have aftermarket LED lights, it may be something else other than the SJB.

If you carpet is wet, uh oh.

 

Huh. Do you think it's worth taking it to ford? Doesn't sound like something I can really diagnose myself 100%. Would it put out a code if that was the problem? I could go get a scanner if so. On the forum I read a guy was throwing the number 400 around for an estimated fix. I'm not going to even bother spending that money to fix something that is merely an inconvenience.

I know a decent bit about the engine itself, but next to nothing about wiring for lights or, radios for example. Is there a specific fuse that could be messed up that I could try replacing? Not too sure if that's how it works but might as well ask haha

Adding this in because someone responded while I was writing the above stuff, nope, no wet

 

If you're not remotely sure about what is causing the issue, then I'd say it's worth paying someone else to fix.

If it's the SJB, then you could be looking at several hundred dollars to replace or even around $1,000. But you can't fix that yourself, as it requires programming.

Electrical issues can be horrible to diagnose in cars these days.

 

lol @ paying 1k for blinkers

I think I'll just say **** it then haha. Thank you guys for your help, if I ever find a solution I'll come back and update.

 

Just because there is no water there doesn't mean that there wasn't before. once it gets wet it takes time to corrode and start messing up circuits. Pull that thing out and actually check it.

 

I haven't looked at one before, but it looks pretty nice to me. I also looked all around as much as I could behind the plastic panel. Everything was clean, nothing was damp, nothing was corroded, barely even any dust, no rust at all even on the bare metal (besides that one nut).