Just because the lights work doesn't mean your battery has enough charge to turn over the engine. Click Click Click is often what is heard if your battery is charged but not charged enough to crank the engine.

1. Charge up your battery or get a jump, if it starts then its not a starter issue (obviously)

2. Drive it for 15 - 20 mins. Then turn it off (preferably back at home) and try to start it again, if it starts then you've got a slow power leak somewhere if it doesn't then you've got an alternator issue.

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2004 E53 4.4L N62