[Turbocpe]

I should state that as far as I understand, this occurs once the speed hits 3MPH or greater. So while you're passing the 3MPH mark, it will occur.

The manual states that you may hear this noise in the engine bay when it occurs. But other than that, you will not know that this occurs because the pump can run and not affect normal vehicle operation while it runs this brief test.

My truck does this every first time I hit 3MPH or greater. At night, I'll see the lights flicker, in additon to almost a crush type sound.