Error Code for Turn Signal and Brake Light Malfunction on both Taillights

[R N M]

Took out my M3 today for 1st time in a few weeks.
The car started right up with no issue.

I drove it about 5 minutes and then started to get the error codes - 1st for the brake lights and then for turn signals. When i turn on the signals, they start blinking fast. All the lights are stock and car has Executive Pack. The car is 2018 with just under 9k miles.

I tried to research on forums but didn’t see any issues like this for M3/4. The F87 M2 has some issues though.

I turned the car off and on a few times, locked it and let it sit. When you turn it on, no errors but when you start driving, the errors start popping up again. Also the errors is for both left and right taillight. I don’t think its a bulb, just strange.

Any suggestions of what this could be and how to resolve it?

[Yuille36]

I'm not claiming to have the answers, but in most cases like these the issue turns out to be battery related. I would have your battery tested, any AutoZone or Advance Auto Parts will test your battery free of charge. Or just take it to your own shop and have them test it.

[alex2364]

Was your car on a battery tender? Either way get the battery checked.

[R N M]

Originally Posted by alex2364

Was your car on a battery tender? Either way get the battery checked.

No it was not but never had issues before.
I believe these batteries are good for 10yrs or so.

The car started up right away with no hesitation but will test battery.

[R N M]

Originally Posted by Yuille36

I'm not claiming to have the answers, but in most cases like these the issue turns out to be battery related. I would have your battery tested, any AutoZone or Advance Auto Parts will test your battery free of charge. Or just take it to your own shop and have them test it.

Any reason why you think its battery related? I’m not saying it’s not just curious how it’s related.

All other functions were working fine including A/C.

Just such a strange issue…

[N1rve]

Originally Posted by R N M

No it was not but never had issues before.
I believe these batteries are good for 10yrs or so.

The car started up right away with no hesitation but will test battery.

I don’t think they are good for 10 years. People have been replacing them much earlier than that.

[R N M]

Update - took the car out again to try to troubleshoot the issue and found more things that don’t work.

Both rear windows are not working. They went down an inch but can’t close them. Front windows are fine.
All other controls like mirrors, A/C work fine even the rear window shade.

Definitely think its battery related issue.
Getting the CTEK charger to avoid this in future.

Should i try disconnecting the battery to see if that helps?