I have a 2011 420 that has some sort of electrical problem. When you turn the key everything acts like it low on power like if the battery would be dead , fuel pump can't run light on dash barley on ect. Now its a brand new battery all the terminals are cleaned. If I jump the started solenid the starter turns over strong, but the motor dont start due to fuelpump not running and no power for spark.I know the ground goes directly to the starter. Then to the frame ... does anyone in here know anything else to check I exhausted everything I know... Could it be a rely or a loose connection in the harness?