11.88 Volts should be enough to keep the truck running. If the truck stalls out then verify you are getting spark by pulling one of the coils out. Insert a spark plug and ground it. If spark is good then verify you have battery voltage to pump at the pink/black stripe wire. If no power then check to see the inertia switch button is pressed in. It is located on lower right side passenger side. Remove the side panels under the glove box to access it. If you do have spark and power to fuel pump then the pump is bad. If no power to pump and inertia is good then check fuse #10 and fuel pump relay.
As for the charging system, you would need to do a voltage drop test on battery cables when it is running. About half a volt (0.50V) is normal. How you check that is you place the positive lead of your DVOM tester on positive cable and negative lead on positive cable of the alternator. Normally you will see 0.02 volts. Check the ground cable by placing positive lead on ground cable at battery and negative on alternator housing like the hold down bolt. If you see anything over 1 volt check for high resistance like corrosion. Have seen people replace alternator after alternator and all it was, was a corroded ground cable at the block.
Attached a diagram for the fuel pump. Hope info helps. And code P1000 just means the readiness are not set because you must of had battery disconnected that it reset the computer.
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Wednesday, August 31st, 2016 AT 3:43 PM