I have a 1997 F150 (4.6 liter) and had a problem starting it a few days ago. When trying to start it by turning the key - only clicking until jumped. I took it to Advance Auto and they checked the charging system and determined that the problem was the battery. Great - replaced with new battery. Ran fine for a day and then last night after being at a store - turn the key and clicking. We jumped the battery and just clicking when trying to start. But, I noticed with the key turned half way and the instrument lights on there was a intermittent clicking with the lights flickering with the clicking. I went under the hood and located the clicking coming from a relay in the master fuse box under the hood. It is the large relay (3rd) closest to the fender. I apologize for being so vague, but I am a novice when it comes to electrical issues. Could this problem be the relay, voltage regulator, starter solenoid or something else ?