one click won't start
 

no warning signs turned the key and heard 1 click, no starter grind or any noise from the starter at all. seems to coming from a unit on the fire wall that is conected to the battery. 6 month old battery.

The usual suspects:

Battery, battery cable, connection, starter relay, starter motor.... etc.

You have to do the needed troubleshooting to determine what works and what doesn't.