So my wife's 2004 suburban 5.3L 4WD tells us "Service Brake Booster" after every start up. The brakes are working perfectly, no fluid leaks can be found, and no codes are set. Any ideas?

Thank you in advance for your help!

 

i have a 2003 Z71 suburban and I was getting the same message just before I had to replace my alternator. After i replaced the alternator, messages went away. Not sure if there are some electrical components in the brake booster that were effected. just my experience, im not a mechanic and dont know a whole lot about cars but thought this might help.