I am not qualified to offer this answer...
The clicking sound will be the relay of the starter motor.
Put the headlights on full and check if they dim in brightness when you try to start.
No dimming means the starter motor is not taking current (power) from the battery - and the motor may be defective.
Any dimming of the lights will suggest that power is flowing and that something is stopping the engine from turning over.
Either way - the starter motor is not turning over when it should.
Good luck...
H Ford, October 2014
