[m666etal]

Two threads already exist for this issue but none of them have any posts where the root cause of the issue was figured out or the dealer fixed it.

Last night I was driving at around 20 mph turned into a parking lot, stopped to back into a spot and the brakes felt weird when I pressed them, like I had to push them harder than usual and some sort of friction and then this message popped up on the dash "Service Brake Assist". The issue went away when I shut down my car and restarted it after 10 mins. Wanted to know if any of you have experienced it recently and is there a fix for this?

I've contacted the dealer and waiting to hear from them.

[oneredry]

mine activated upon me (sorta hard) on the brakes upon slowing down from 110ish. took it to the dealer the next day and verified, nothing came about it and they just reset the code. didn't tell me what the root cause was.

[m666etal]

Originally Posted by oneredry

mine activated upon me (sorta hard) on the brakes upon slowing down from 110ish. took it to the dealer the next day and verified, nothing came about it and they just reset the code. didn't tell me what the root cause was.

Thanks for the update. My dealer said if it happens again book an appointment so they can give me a loaner and look at it . They'll just have a joyride in my car since this cannot be reproduced on the fly.

It's scary to think the brakes failing like this on the freeway at really high speeds!

[m666etal]

I went to the dealer and told them about this issue. They said there was a bulletin form GM about this issue and have reprogrammed the module with GM's update. attaching a picture of the same. Anyone who is still having this issue can show this information and maybe the dealer can help you out.

[BOYD3800SII]

Originally Posted by m666etal

I went to the dealer and told them about this issue. They said there was a bulletin form GM about this issue and have reprogrammed the module with GM's update. attaching a picture of the same. Anyone who is still having this issue can show this information and maybe the dealer can help you out.

THANK YOU!!!!!!!!!!

[CowmaroV8]

I just experienced this issue and thanks to checking in the forums here had it taken care of with a service bulletin. I understand this is an old forum, but with low mileage cars still out there, this issue is still very real in 2020 and I wanted to help anyone I could.

My brake assist warning came on and I lost about half my braking pressure and it felt that ABS was on 100% of the time. This is mentioned in the owners manual as normal behavior when the service message occurs.

I turned the car on the next day and the issue was gone but took it for service anyway. They told me there was a service bulletin and they will simply run a diagnostic and if no issues are found other than the TSB then that's all they will charge. It happened 8 hours prior the night before the computer had all the error codes stored so they were able to pull them up without any active CEL or Error Codes.

Should be a recall and not a TSB but just needed to share this as these forums are the reason I knew of the fix ahead of time. Maybe a diagnostic fee is worth the piece of mind to get the update needed rather than waiting for the brakes to fail in traffic as mine did.

"Internal software fault in EBCM. Reprogram EBCM per BULL#17-NA-048"

[F419sr1]

Originally Posted by CowmaroV8

I just experienced this issue and thanks to checking in the forums here had it taken care of with a service bulletin. I understand this is an old forum, but with low mileage cars still out there, this issue is still very real in 2020 and I wanted to help anyone I could.

My brake assist warning came on and I lost about half my braking pressure and it felt that ABS was on 100% of the time. This is mentioned in the owners manual as normal behavior when the service message occurs.

I turned the car on the next day and the issue was gone but took it for service anyway. They told me there was a service bulletin and they will simply run a diagnostic and if no issues are found other than the TSB then that's all they will charge. It happened 8 hours prior the night before the computer had all the error codes stored so they were able to pull them up without any active CEL or Error Codes.

Should be a recall and not a TSB but just needed to share this as these forums are the reason I knew of the fix ahead of time. Maybe a diagnostic fee is worth the piece of mind to get the update needed rather than waiting for the brakes to fail in traffic as mine did.

"Internal software fault in EBCM. Reprogram EBCM per BULL#17-NA-048"

I had the light and lost all boosted braking. This has happened twice so far. They said the booster had hydro locked with oil. When I picked it up last time the light came on on my way home. They have no idea on why this is happening