Battery being drained

I have a 2000 ford explorer sport. For some reason the battery is being drained when my wife runs errons. It will start fine and she can make a couple stops then it will be dead. Is this just because the battery won't hold much or a charge anymore? This is the original battery. I checked the cable and they looked fine. It will charge up so she can start the next morning but like I said. If she has to make a few stops it goes dead. Any Ideas before I start re-building the whole thing?...:biggrin:

13 year old battery? It's probably won't keep a charge.

I just got back from having the alternator and battery checked...Both checked out in good working order. the tech said he may think that when the car is turned off the alternator has bad diodes and is sucking juice off the battery. He had noway to check that. Is that a possible issue? How expensive is that to get checked if I take it to a shop?..

I just got back from having the alternator and battery checked...Both checked out in good working order. the tech said he may think that when the car is turned off the alternator has bad diodes and is sucking juice off the battery. He had noway to check that. Is that a possible issue? How expensive is that to get checked if I take it to a shop?..

I would guess a testing method would be to disconnect the battery completely. Measure the voltage. Let it sit for 24 hours and measure it again. If the voltage remains the same, I would do the same test except with the battery hooked up.

Yes it can drain the battery. No idea about cost to test. Look for an alternatory, starter, generator repair shop. They also will probably be cheaper if you need an alternator.

You can test like aleekat sez but run the car tonight,headlights on the garage door or somthing. Rev the engine up and see if the headlights flare up brighter with high RPMs.If they do that's a sure sign of bad diodes in the alternator. If so don't scrimp on a cheapo,chiwaneese alternator. They're marginally rebuilt and they don't always replace a bad diode. Theres 3 diodes in 'em and they'll work OK till 2 of 'em go bad.