This vehicle has no comm with ecm and is a cranking no start. The instrument cluster display shows comm fail with ecu. There is an eecu 20 amp fuse in the underhood fuse/relay center that only has 2.7 volts at it. If I apply 12 volts to this fuse we have comm, truck starts and runs. Can anyone tell me where this fuse gets its power from?

Andrew Mcmillan
Technician
Twin City Fleet Repair
Minneapolis, Minnesota, USA