Rick's Free Auto Repair Advice

Posts Tagged: C027B

C027B Low Brake Pedal

Why are you getting a C027B Low Brake Pedal code after replacing a master cylinder   GM has issued a service bulletin #PI0785B to address a C027B code that appears after replacing a master cylinder on the vehicles listed below. GM says the C027B trouble code is most likely due to a missing O-ring that fell off during the master cylinder replacement procedure. The missing O-ring results in a vacuum leak between the vacuum brake booster and the master cylinder causing a low brake pedal and the trouble code. To … Read More

Low brake pedal GM

Fix a Low brake pedal GM – C027B GM vehicles If you encounter a low brake pedal or one that sinks to the floor and you’ve either done a repair or had a repair done lately where the master cylinder has been moved, the problem may be as simple as a missing O-ring. GM installs an O-ring between the vacuum booster and the master cylinder. But if you remove the master cylinder without first pumping the brake pedal several times to discharge the stored vacuum, that can dislodge the O-ring. Replace … Read More


Custom Wordpress Website created by Wizzy Wig Web Design, Minneapolis MN