SERVICE BRAKE ASSIST / 2020 SIERRA

[hdbrad]

My Brand new Trailboss had the same failure leaving from my purchase. Not real happy. They found 2 ground bolts behind Air Cleaner that weren't torqued properly. No codes since repair.

[BSav]

Truck has been at dealer over a week now.   Just got parts to replace master cylinder.  Do the brakes drag while this code is active ? Or what causes the code anyone know?  Truck had bad fuel mileage for the day and half until I brought it in and would slow down quite quickly when letting off gas.   Front rotors looked like they had some pitting from it.   Chev won’t take ownership to replace them for the unnecessary wear after they Re flashed to fix three times before doing master cylinder.  Not happy 

[Elvis73]

Brought my 2020 Sierra Elevation(6K miles) to dealer service today(truck was purchased March 2020).   The Service Brake Assist notification came on three different times in the last 1.5 months and then went away without any service.  There have been no issues with the brakes or the truck but I decided that this needed to finally be looked at by my dealer.  After 2 hours, they said they noticed a code but they could not replicate the code or what was causing this code.  Dealer asked me if I was hard braking or carrying a heavy payload - answer was "No".  After another hour, they decided they were going to keep the truck overnight to "go to sleep".....They will also order a new master cylinder and most likely replace the master cylinder tomorrow morning.

The dealer response was not a definitive response regarding knowing the true issue why this SBA notification keeps coming on.  Based on previous readings, many issues have been had with previous years braking systems on these GM trucks.  I hope after this MC replacement, this takes care of the issue....

 

Edited March 25, 2021 by Elvis73
misspell

[Corey A F]

My 2020 Silverado service trailer brake system, ESC, ABS, and traction control system lights came on. I got a 6” lift 2 weeks ago and then all these lights came on. Anyone know if it’s my lift or does anyone else have these same problems ?

[gmdob]

2021 GMC AT4 with less than 1,000 miles on it.  Had it into the dealer for a noisy AC compressor.  They replaced the compressor.  That didn't fix the problem so they replaced the TRX valve.  That still didn't fix the noise but when I drove it home that night I got the pop up message "SERVICE BRAKE ASSIST" and now I'm getting bombarded with email and text messages from GM Diagnostics to have it serviced within the next 7 days.  Back to the dealership I go.  It's a 25 mile round trip from house to the dealership and this will be the 5th trip.  This is really getting old.