Recently purchased 2016 F150 and been to the dealer twice now, said they can't find anything, feel like there's a communications problem somewhere, any ideas how to diagnose or where to start? Shouldn't a Ford dealer know? I charged the battery which is only 2 years old, and then had a local guy read the codes and print a report which basically called out communications errors. Thanks!
These are the warning lights on the dash that came on two different times.

On left side of screen

• “Brake System”
• “Electric Park Brake”
• “Traction and Stability Control”
• “Fasten Seat Belt”

On right side of screen

• “Anti Lock Braking System”

Center Display Screen errors

• “Hill Start Assist Not Available”
• “Park Brake Limited Function, Service Required”
• “Check 4x4”
• “Steering Assist Fault, Service Required”
• “Park Brake Malfunction, Service Now

 

It’s probably not it but I’d load test the battery. A weak battery can cause screwy problems like you are having. I know it’s a newer battery but I’d still LOAD test. Load test is critical because voltage alone doesn’t tell the story.

The dealer can’t find a problem? All those codes didn’t tell them anything? As you are aware they are putting you off. They got your money and lije it if you went away.

 

Just a WAG, how about the ABS speed sensor on one of the rear brakes?