Need some help. Battery is randomly being drained while not in use. About a 1.5 months ago, my '97 F-150 5.4L would not start. Jumped it (in major cold winter blast) and let it warm up for a few. After about 20 minutes, it stalled and would not start on it's own. Since this occurred while running, I assumed the alternator was bad and took it out to have it replaced. It was tested and was fine. Jumped the truck again and started fine for about a month and a half. Randomly the other day, I went out to start it and the battery was completely dead. So I assumed the battery must be bad as it isn't holding a charge. Took it in to be tested and it was fine. I then checked to see if there is a draw from somewhere by turning everything off and touching the positive terminal to the post. Definitely a spark there. So there is a current draw coming from somewhere, but all connections seem clean and tight. Ford dealer has it now, but can't find anything either. Any thoughts or suggestions???

 

Google the issue. You will find some surprisingly detailed information. Many of the tests are simple and easy to make and could save you som money.

 

How old is the battery... if you dont know .. or its pretty old..i would replace it.. Also these trucks have a bad windsheild leak.. from the factory.. it allows water to drain into the GEM module... and the fuse box... the GEM module will make lights and blower motors run.. when the truck is off...

 

Battery is just over a year old, and has tested fine both by NTB and Ford Dealership. Same with the alternator. Ford Dealership had for 2 days and couldn't find anything. Gonna get a test light and start pulling fuses I guess.

 

As I stated in another thread- you can test for battery drains by disconnecting a battery cable and place in-line between the cable and battery post a test light or ammeter. The light should not glow if there is no drain but may slighly glow if you have memory on your seats or radio. If the light does glow brightly, start pulling fuses. When you get to the problem spot the light will go out or glow a little. If using an ammeter the reading should not be above .5 amps. this allows for memory power seats, etc.