What does the Auxiliary battery on a 2006 Sprinter 3500 do?

The Blower fan works for about 10 minutes and then turns, of i think it might be the battery.



Thank you!What does the Auxiliary battery on a 2006 Sprinter 3500 do?
An auxiliary battery allows you to run more electrical items when at a lower speed. Generally it makes sense to upgrade the alternator as well. Sprinter can get optioned with up a 200amp alternator. Stock is 90, then 110, 145ish and then 200. If you plan to use the sprinter as say, a TV on site vehicle, or for other media relations then the extra power is more beneficial to run the equipment with the vehicle at idle speed rather than revving the engine to maintain a charge.



Blower fan is controlled by the blower motor resistor pack. It's just a small relay like item under the passenger side dash board. Generally when its on it's way out, you cannot use lower fan speed settings - high only.