Join Date: Sep 2011
Thanked 264 Times in 203 Posts
Get a volt meter so you know what's going on.
Check the battery voltage before starting - it should be 12.7V or more. Then check it as you are cranking - it should be over 10V.
If that's good, start the engine and check the voltage - it should be over the voltage before starting and around 13V.
Then rev the engine to 5000 RPMs and check - it should be in the 14V range.
It may be a battery problem, battery connection problem, other wiring problem, or charging system problem.