Tail lights sometimes not working

[Malithos]

I have a 2016 and the tail lights every once in a while one bar goes out. It’s always the same. Either the driver side middle bar or the passenger side outside bar.
I have found that if I restart the car it works fine afterwards.
Anyone have any ideas why this is happening?

Video I took this morning of it happening:

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[SteveW]

What fixed mine was having the dealer flash the latest update to the BCMB module.

 

[Mr. Met]

I am not sure, but I do believe they cant be serviced only replaced. Are you still under warranty?

 

[69mach1-395]

I think this is what happened to me recently, kind of worried since warranty is almost done.
What is the BCMB module?

 

[ugstang17]

Its a body control module. There are likely several in the car. Since I have no access to a 15+ wiring manual I have no means of telling you more. My wife's Fusion had two of these fail. The symptom was a non working passenger side window - thankfully it was up. Unfortunately as I understand it (unless its bs to get a service fee) the device has to then be programmed to communicate with the car after install. I took the two units apart and saw nothing that appears to be a programmable microprocessor inside. However that does not mean that the devices have static addressing which may require re-addressing on the car side to establish communication.

Often times a reflash update will be covered on a case-by-case recall or tech bulletin. A respectable dealer will tell you this knowing they get paid either way if covered...even if the car is outside the 36-36. However if not as was the case of our Fusion it is NOT part of the power train extended coverage as we found out...and which I expected.

Cost of each module from the dealer was $37.00 as I recall. Price may vary depending on year/make/model/location. Hope this helps.

 

[SteveW]

Here is a thread on the issue and in there is a reference to an old SSM that addressed the problem. It is no longer on the Ford system so no warranty at least for me.

https://www.mustang6g.com/forums/threads/tail-light-out-then-back-on.101551/

When I brought the car in I told them if they couldn't duplicate the problem I'd pay them for the BCM flash. They couldn't and I paid for the flash. No problem since.

 

[SteveW]

@Cobra Jet figured this out at his dealer:

The Service Dept’s can’t find that original SSM 45895 because it’s been supercded by SSM 47429 (which is the Official Ford SSM I have attached).

https://www.mustang6g.com/forums/threads/tail-light-out-then-back-on.101551/page-2#post-2393882

 

[Blackbeauty]

That happened just one time to me completely randomly and never happened again. Been wondering wtf that was ever since. I had just gotten a car wash and though maybe water got in the taillight housing and causing a short on one of the lights, but numerous car washes later, still hasn't happened again.

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