If it's under warranty, and it looks like it should be, Make the dealer fix it, VPWR= Vehicle power, supplies power to your computer. Is it gas or diesel? If it's fuse F74 there is a tech bulletin about it, heres the bulletin:
6.4L - INTERMITTENT NO START / LACK OF POWER - DTC P0003 AND/OR BLOWN FUSE 74 - BUILT PRIOR - 8/20/2007 TECHNICAL SERVICE BULLETIN Reference Number(s): 07-26-2, Date of Issue: December 24, 2007 Related Ref Number(s): 07-26-2 ARTICLE BEGINNING ISSUE Some 2008 F-Super Duty vehicles built prior to 8/20/2007 equipped with a 6.4L diesel engine may exhibit a lack of power or no start with possible DTC's P0003, P0004 and P0091 caused by circuit CBB12 at the high pressure pump gasket grounding to the high pressure pump body (may also result in fuse 74 being blown). ACTION Follow the Service Procedure steps to correct the condition. SERVICE PROCEDURE 1. Unplug connector C1926 near the high pressure fuel pump cover. 2. Check pin 4 green/white and pin 2 yellow wires for a short to ground. a. If either one is shorted to ground, remove the high pressure fuel pump cover and replace the pump cover gasket/harness that contains the grounded wire ONLY. The high pressure fuel pump does not need to be removed and replaced. Refer to the Workshop Manual (WSM), Section 303-04C. b. When removing the low pressure fuel lines and high pressure fuel tubes from the high pressure pump, use a back up wrench on the high pressure pump fittings to make certain that the fittings are not loose as the cap nuts and high pressure fuel tubes are removed (this may cause a fuel leak). c. When installing the new high pressure pump cover gasket/harness, verify that the VCV wires are wrapped in either high temperature convolute or a mesh style abrasion wrap. d. When making electrical connections to the high pressure fuel pump, pull the connectors to verify connectors are locked in place. PARTS INFORMATION FORD: 2008 F-Super Duty Page 1 of 1 3/14/2010 ...
Sunday, March 14th, 2010 AT 9:21 AM