Edmunds Answers



  • karjunkie 08/19/09 9:30 am PST

    You have what we call parasitic drain. This means one of the electrical systems is drawing electrical current even when the vehicle is turned off. To trace it you'll need to use an ammeter or multimeter you can get at any auto parts store. Remove the negative side battery cable from the negative battery terminal. Attach an ammeter between the negative cable and the negative battery post. Wait a few seconds to several minutes for the car to go into sleep mode. i.e. when you make the contact with the test light the cars computer systems "wake up" after a bit of time they will go to "sleep". If the ammeter is reading over 25-50 milliamps, something is using too much battery power. Go to the fuse panel(s) and remove fuses, one at a time. Pull the main fuses (higher amp ratings) last. Be sure to observe the ammeter after pulling each fuse. Watch for the ammeter to drop to acceptable drain. The fuse that reduces the drain is the draw. Consult the owners' manual or service manual to find what circuits are on that fuse. Good luck!


Top Electrical Battery Experts View More

Rank Leader Points
1. MrShift@Edmunds 1610
2. zaken1 1085
3. karjunkie 815
4. tony78 300
5. 0patience 225
6. Stever@Edmunds 165
7. Mr_Shiftright 160