Starter will not engage

[av8or91]

I have an 03 6.0 and the starter sometimes just does not want to engage. I can hear the relay clicking in the dash, and I sometimes can hear the solenoid click on the starter. Right now I it will not click on the starter only the relay in the dash. I have unplugged the yellow wire on the passenger side and connected that to the battery for a start and it has worked but now it wont do anything. Not sure if this is just a starter issue of the solenoid on the charger. I have done some reading and was reading about the fan clutch sensor, if that fails it will not allow a start but dont know much about it. Any ideas appreciated!

[dannyboy950]

Check your wireing and connections for corrosion/tightness. Batteries fully charged, have they been load tested lately? You need a min. of 11.5 volts to start at starter.
Less than 10v starter will not work. Less than 8v PCM and FICM will not work.
Proper voltages on a 6.0 are essential.

[Mikey's250]

Yep check batteries. I had the same issue once every 6 months then every three them ever day until it finally quit completely. New batteries fixed it

[av8or91]

Battery voltage is good on both batteries, just replaced them a couple months ago when this issue started.

[av8or91]

Turned out to be the starter. After a few hours wrestling with the top bolt on the starter, and installing a new one, it fires right up.