This bulletin applies to 2011-2013 Cadillac Escalade models. You may receive a vehicle with a concern of an audible engine whine noise at 1,500-1,800 rpm. The noise can be heard inside the vehicle at or near the right side of the dash/bulkhead area.
If this is encountered, follow these steps:
1. Verify coolant level.
2. Remove the serpentine belt to verify if the noise goes away.
3. Rotate the thermostat 90 degrees and re-test.
4. Replace the thermostat and re-test.
5. If thermostat replacement made no change, replace the water pump.