Vehicle: 2019 Chevy Silverado 1500, 2WD, L4-2.7L Turbo, Automatic Transmission/Transaxle

Mileage: 69,253 miles

Problem: The customer accidentally tore off the right rear brake hose. The technician replaced the hose and vacuum bled the rear brakes. He erased diagnostic trouble code (DTC) C05B0. The brake pedal height felt normal, and the brake, ABS and traction control warning lights went off.

When he started to back the truck out of his stall, the brake, ABS and traction control warning lights came back on, and the brake pedal height dropped about halfway down. Diagnostic trouble code C05B0 returned.

Case Details: The technician tried bleeding all the wheel cylinders, but that only caused the brake pedal to sink all the way to the floor. The pedal would only pump to about halfway up. At this point, he made a call in to ALLDATA Tech-Assist.

The consultant advised to make sure no brake fluid was leaking. If there were no leaks, he advised disconnecting the negative battery cable for a few minutes then try bleeding the brakes again. Sometimes the control module stores the fault and won’t reset until you unplug the battery.

If that didn’t help, he advised to try updating the K160 brake system control module (BSCM) calibrations with the latest calibrations available in Tis2Web.

Confirmed Repair: The technician cleared the DTC and turned the engine off. He disconnected the battery for 5 minutes then pumped the pedal as high as it would go. Next, he connected the battery and pumped the brake pedal up again. While holding pressure on the brake pedal, he started the engine again and looked at pressure data on his scan tool. He pumped the brake pedal twice and the pedal came up completely. The lights went off, and pressure equalized at 710. He erased the DTC then went for a test drive. The brakes worked perfectly. Successful fix!