Upon turning the ignition this evening my truck just clicked once each time I turned the key. I popped the hood made sure the battery cables were tight on the post and it turned right over. I then turned the heat on and the truck instantly died. Now it wont do anything, no lights, no sounds when I turn the ignition, nothing. It acts as if there is no battery in the truck. Battery is new as of July with a manufacturer sticker of 5/12 and the alternator is new as of last month. Any ideas???

 

Could be a bad connection... battery cable at the battery, battery cable at the ground (engine block). Could be corrosion inside a battery cable. Could be a defective battery. Have you measured the voltage? Both with everything off and while cranking the starter?

 

Bad connection truck died because the alt was supplying all of the power. clean battery post connection good and put elctrical grease on the post that helps alot.