[PorscheFred]

Update:

I know is an old post but, just as it did for me, somebody will find it useful.

It was the LED lights. In summary, replaced the brake light switch (although the old one tested fine) and the problem continued. Just to test, I replaced the third brake lights back to the incandescent bulbs, reset the code and it has not come back.

I also found some non-Porsche related posts in another forum about similar problems and describes a fix using a 50W 30A resistor inline with the third stop light or one of the main stop lights. Seems like older car with CAN bus suffer from this. Maybe the ABS computer is expecting a specific draw in power from the stop lights and throws an error code when the draw is lower than expected.

For now, I went back to replacing the third brake light bulbs back to incandescent while leaving the rest on LED. I ordered an inline 50W30A resistor (very cheap on Amazon) and will test the fix when it gets here.

Hope it helps the next guy down the line.

Regards,