Disabled Sequential Tail Lights
 

Hi guys!

I recently purchased an imported 2015 GT here in Switzerland. For some unknown reason, the previous owner had disabled the sequential turn signals, which sucks cause they have to be one of my favorite "quirky" features of the car (insert Doug DeMuro reference here).

Does anyone one you have an idea where I could look/what might have been done to the lights? I removed the rear panel and checked the wiring, couldn't see anything that indicates it might have been tampered with or anything.

Cheers, Vincent

I just figured it out, thanks to a user on another forum. Turns out, they changed it using ForScan, changed it back to the stock value and now they light up like they should :)

I have the same issue. Would be great if you could post the value you changed with ForScan

It wasn’t changed using ForScan afterall. The value you’d be looking for is 7B7-03-01. x0xx xxxx disables them, x1xx xxxx enables the sequentials.

In my case though, they physically changed the wiring, basically soldered in an extra copper wire going to 2 of the 3 LEDs (on either side) and attached a relay. Was a pain in the *** to get everything back off but all I had to do really was remove the 2 relays. After that, they lit up sequentially again, like they should lol.

They also did some funky stuff to the front parking lights. They disabled them and had both bulbs act as the turn signal.

Let me know if ForScan does the trick for you.
Where are you from if I might ask?

Hey cool, thanks for quick response. I'm from Switzerland too and driving an US imported Mustang GT / 2016.

I already did some other modifications with ForScan, so I just tested the value right now. Unfortunately, the value was already set to x1xx = enabled. So I assume it’s similar as described from you, means they attached a relay instead changing the value. I’ll have look at the weekend on the cabling staff.

Anyway thanks for help.

Haha, yup. Same case here. Did Engel do the import?

it’s not that hard, can probably be done in 20 minutes if you know what you’re looking for. I can definitely help you with that if you want.

What canton are you from? I’m from st. gallen haha

Yep, imported by Engel. I live in Aargau, near Zurich. Your offer is highly appreciated, I’ll come back to you if needed.

btw, next Sunday will be a Ford meeting, I’ve planned to be there if weather is not too bad.

Ah ****, I’m gonna be in the Netherlands over the weekend unfortunately :/

If you ever see a black ‘15 Performance Pack GT with RTR axlebacks and no front plate, that’s me haha

Hey just a stupid question, where are the relays located?? I expected to see it from the trunk side when removing the panel. Do I have to remove the lights as well??

And I found this – Link, I guess this is what I have to do?

Just typed in everything step by step but my browser crashed :fuss:

anyway, here we go again:

after you pull off the rear plastic trunk cover using the 4 thumb screws, you’ll have to remove the subwoofer (if you have the shaker audio). Pretty simple, just take out all the torx screws and the connector at the back.

Now you’ll have to pull back the carpet quite a bit on the right side. You may even need to undo a clip on the top to get it back far enough. You should see a black plastic box, the body control module B (BCMB) screwed on in a keyhole behind the frame with 2 connectors plugged in. Follow the cables and you’ll see the harness. It’s most likely covered in fabric tape. Btw, whenever you see that fuzzy fabric tape, it’s been messed with by Engel. Parking lights and front HID washers for example.

Just unwrap the tape and you’ll see the soldered in cables and the 2 relays. They were never there, so you can just remove both and call it a day. Or cut off the extra cables if you wanna please your OCD. I used some electrical tape to wrap the harness in again after.


That should do the trick! Let me know the result :)
if you wanna get the front marker & parking lights to work again let me know.


https://cimg4.ibsrv.net/gimg/themust...523c10254.jpeg
https://cimg0.ibsrv.net/gimg/themust...6533c6176.jpeg
https://cimg8.ibsrv.net/gimg/themust...809176c56.jpeg
https://cimg1.ibsrv.net/gimg/themust...370bfbbb9.jpeg

Wow, many thanks for the description and pics, that helps a lot. I'll let you know about the outcome.

I just want to inform you that I removed both relays as described from you. I was easy and went well. I cleaned up this cable chaos and isolated everything new. Sequential tail light is now back and works perfect!

I also tested disabling / enabling sequential light using ForScan on the “7B7-03-01. x0xx xxxx” value. I can confirm this works great. Set “0” disable it, set “1” does it enable again. So that’s a cool hack and allows easy to change if needed (e.g. CH regulations / MFK).

Thanks again for your support, it was a great help.

Awesome! Glad I could be of help :)

Hi, do you need extended licence in Forscan to do this? I've got the ELM327 with HS/MSCAN switch and connected to the car however unsure where to look for the codes. Could I be cheeky for a step by step guide at all?

Sure thing haha :)

Yeah, you will need an extended license as far as I'm aware - but not completely sure I might be wrong.

Just plug it in and connect your laptop. Switch the switch (lol) so you are able to access the BCMB values.
Search for 7B7-03-01 x?xx xxxx and replace the "?" with 0 for off (not sequential) or 1 for on (sequential).

I haven't messed with forscan in a while, this is just off the top of my head.

Hi, so I connected again now I have the extended licence.

From the screen print BdyCM is the module which relates to BCMB. As you can see though when I pressed the play button (start service) on that module it went through some numbers and then said my battery needed more charge.

https://cimg5.ibsrv.net/gimg/themust...85a3b760cf.jpg
https://cimg6.ibsrv.net/gimg/themust...50130f909b.jpg

So I managed to find the other modules, first BCMB module contains 737-03-01 setting.

I changed the 0 to 1 and nothing happened, checked it updated etc.

Still only have one tail light on indicator - outer one.
https://cimg8.ibsrv.net/gimg/themust...c8de03b0cb.jpg
https://cimg8.ibsrv.net/gimg/themust...b425fad306.jpg
https://cimg2.ibsrv.net/gimg/themust...e94838c502.jpg

The value works, I've tested it several times, at least on my 2016 Mustang (US version) . What kind of a Mustang do you have, respectively where do you live? If you live in Europe and you drive an imported US Mustang there might be some additional releais installed in the trunk - see pictures above.

Hi

I'm in UK. Assuming I dont have the sequencers on a european model so might need a wiring harness from ponymods or something.

Jason

Correct, I think that's the problem. UK & Europe Mustangs are slightly different from the US version, especially the taillights. Only the US version has sequential flashers, but the UK & Europe models do not. I have an US Mustang but imported to Switzerland, so that's why the value works.