New Battery problem

I have a 2004 Ford Focus. It has a new battery and every 2-4 months it just stops working. The battery and starter and alternator all check out ok. The car just does not start and when I turn the key it just has that clicking noise. I have AAA come to jump the car. It starts immediately and go on my way for another 2-4 months. I have done this a few times and feel that it might be a short somewhere that drains the battery 100%. So before I sit at the dealer’s place or go to another reputable mechanic I thought I would ask you what to do.

After all I have been listening to you Click and Clack boys for over 20 years and laughing my head off with your NPR program.

I feel that some time in one’s life they will need to finally contact you with a car problem.

When you just get the clicking noise but the car starts when jumped from another battery, full power is not gettng from your battery to the starter. Remove the cable clamps from the battery, clean the terminals and see what happens. When this happens, try tapping on the battery posts with the handle of a screwdriver and try the starter again.

The trouble you are having may not be with the battery. The next time this trouble happens see if the headlights and blower work ok. If they are fine then the trouble may be with the neutral safety switch. Try moving the shift lever around in the PARK mode while trying to start the engine or try to start the engine while in the NEUTRAL position. If either of those things work then the trouble is with the safety switch.

I have had a couple of neutral safety switches fail and both of them wouldn’t start in neutral either. To make sure of my diagnosis I pulled the plug off the neutral safety switch and put a jumper wire between the two appropriate terminals. If the car starts fine after that I replace the switch. On my cars you won’t have backup lights while the plug is off.

You might have what is called a “parasitic drain” that discharges the battery under certain conditions…Alarm systems, a stuck automatic door lock, a hidden light that stays on, trunk, under hood, glove box…Any good mechanic can connect an ammeter between a battery post and it’s cable and read any draws on the battery… Fuses are then pulled one at a time to isolate which circuit is draining the battery…