Sounds to me like your problem could be the fuel pump relay. You'd be surprised how many components it powers up. I checked the schematic a while back and noticed that the window regulator ECU is effected by it and the doors latch mechanism also. The fuel pump relay also has a signal coming from the main ECU if you're involved in a crash. U might consider replacing the fuel pump relay.I installed a new battery and still had issues. I installed a new alternator and still have the issue. I just checked and there is 13.8V at alternator, but only 11.2V on the battery itself. I need to find out why it is not getting from alternator to battery.