Hi everyone new here I have a 2008 lucerne with a 4.6 it's been acting up while driving would just stall but would usually start back up yesterday it stalled and now has a no crank situation scanner shows no communication with ecm tcm and couple other modules I have no power to the no. 1 fuse ecm crank fuse I replaced ignition switch with no luck security light goes out few seconds after key is tuned on so no issues there gauges aren't working everything else seems to work all lights windows radio ECT any help as to check would be greatly appreciated thanks

 

A no communication problem can be from no power avail to scanner.
Do you have any kind of electrical test equip like a multumeter?

 

Yes I've done power and ground checks to the ecu and tcm can bus check at the diagnostic connector I've got 120 ohms with key off should be around 60

 

Did you get it to start or what's up