Where is the glow plug control module located on a '08 2500 sprinter 3.0 TD? on 2008 Dodge Sprinter 2500

The glow plug light and code P0670 comes on and off intermittently and after reset may come on after several miles. I'm new to these over-controlled MB products and trying to find my way around!

Asked by for the 2008 Dodge Sprinter 2500