2012 Chevrolet Avalanche Owner's Manual - Page 291

Driving and Operating Service Four‐Wheel Drive If the SERVICE 4 WHEEL DRIVE message stays on, you should take the vehicle to your dealer for service. See "SERVICE 4 WHEEL DRIVE" message under Transmission Messages on page 5‑40. Shifting Into Four-Wheel Drive High or AUTO (Automatic Four-Wheel Drive) Turn the knob to the Four-Wheel Drive High or AUTO position. This can be done at any speed. The indicator light will flash while shifting. It will remain on when the shift is completed. Shifting Into Two-Wheel Drive High Turn the knob to the Two-Wheel Drive High position. This can be done at any speed. The indicator light will flash while shifting. It will remain on when the shift is completed. Excessively shifting the transfer case into or out of the different modes may cause the transfer case to enter the shift protection mode. This will protect the transfer case from possible damage and will only allow the transfer case to respond to one shift per 10 seconds. The transfer case may stay in this mode for up to three minutes. 9-41 Brakes Antilock Brake System (ABS) This vehicle has the Antilock Brake System (ABS), an advanced electronic braking system that helps prevent a braking skid. When the engine is started and the vehicle begins to drive away, ABS checks itself. A momentary motor or clicking noise might be heard while this test is going on, and it might even be noticed that the brake pedal moves a little. This is normal. If there is a problem with ABS, this warning light stays on. See Antilock Brake System (ABS) Warning Light on page 5‑21.