Circuit/System Verification

WARNING: This page is about a different car, the 2011 GMC Yukon, 2011 Chevrolet Tahoe, and 2011 Cadillac Escalade. However, it is still accessible from the selected car via links, so may be relevant.

Ignition ON, perform the ABS Motor test with a scan tool. You should hear or feel the ABS pump motor turn ON and OFF.
- If the pump motor does not turn ON and OFF, refer to Circuit/System Testing above.

NOTE:

To ensure the complete brake modulator and high pressure accumulator pressure relief procedure is allowed to occur, the brake controller must see one brake pedal apply with the engine running followed by a proper shutdown without applying the brake pedal.

Transmission in PARK, engine running, apply and release the brake pedal.

NOTE:

The ignition must transition to the OFF position without pausing at ACCESSORY and without applying the brake pedal. This ensures that the brake modulator and high pressure accumulator relief occurs. This process will take approximately 1-2 minutes.

Ignition OFF, key removed from the ignition, wait 2 minutes.
Ignition ON, observe the scan tool EBCM, Accum. Pressure Sensor parameter. The Accum. Pressure Sensor parameter should be greater than 11, 000 kPa (1, 600 psi) in less than 15 seconds.
- If less than 11, 000 kPa (1, 600 psi) or it takes longer than 15 seconds to build pressure, refer to Brake Hydraulic and Assist System Diagnosis (Two-mode Hybrid) .