Check your cable connections to the battery.... disconnect from the battery, then charge battery. reconnect and should be fine also you may want to check the wireing to the starter if these dont fix the problem smack the starter with a hammer if its carrroied up inside that should let you start it if wires are good at battrie slionid and starter replace starter
Defective alternator or bad battery.
Charge or replace the battery.
the battery is dead. charge it. if the battery won't charge buy a new one.
bad battery
It means either the alternator or the voltage regulator is failing, assuming your electronic instrument cluster isn't going bad.
Have the alternator tested.
Check battery, charge it or change it. Dead battery.
Its likely either the battery connections (terminals) are dirty, or where they connect is...or the battery while showing a charge is bad when on a load. If it starts with a jump from another car...it's the battery.
On a 2006 Lincoln Navigator : # 106 is a 30 amp maxi fuse for the ( trailer tow battery charge relay , trailer tow 7 - wire connector , battery charge )
The nominal voltage for just about any car is 14.4. you will find though most cars should run 14 to 14.5 13.5 is kinda low but it is still putting out charge.
I would suspect the battery has been discharged, is defective, or you have loose or corroded battery terminals. Remove and clean the terminals and if that does not solve the problem charge the battery with a battery charger. If it will not take a charge then replace the battery.
Does the engine turn over and then make the clicking noise while trying to start, or does it not do anything but make the clicking noise when you turn the key. If its not turning over at all then it might be a battery problem, Try cleaning the battery terminals, and/or charge the battery, Could also be the starter solenoid, but start with the battery first.