How to find a drain...

[ChevyKev]

Working with Nates/Dovers/Marks/Justins old Jeep - now it belongs to a friend of mine named Thomas.

It drains the battery overnight. Somehow - somewhere.

How do you find an electrical drain when nothing is obviously on?

[93hummer]

Are you sure the battery itself isn't bad? Batteries lose power with the cold temps we are having and if it had even one bad cell.... it would drain overnight. If the battery is in fact good, then one way you could troubleshoot would be to see what portion of the electrical system is draining it... a tedious process. I am curious how much current the system is drawing with everything off? You would need a good multimeter and lots of time to firgure this one out.

[akdsmer]

Slip an inductive amp clamp around the positive battery cable. Measure amperage draw. No draw and draining battery=bad battery. If there is a draw, simply remove the fuses and/or fusible links 1 at a time noting which 1(s) contribute to the draw. Then follow the wiring diagram, unplug individual components until source is found. Old Jeep=15 minutes if a good diagram is available.

I would be looking for things like glovebox lights, brake lights stuck on and bad ignition switches.

Don't have a amp clamp? Remove either side of battery (should always remove negative first) and place a testlight in between battery and cable (in series). If the lamp lights up, then there is a draw, the brighter the light, the bigger the draw. remove components watching light brightness. Once it's off, there is no longer a noticable draw, although a small draw may still be there, but no illuminate the lamp brightly enough to notice (don't place your droplight next to test light).

While you may looe some CCA's you should still have good voltage on a battery, even if stored for weeks. A draw can come from an internally shorted battery or more commonly, across a acidic/dirty battery top. Clean the battery top to ensure there is not a path for the electrons to travel across.

[ChevyKev]

Battery is new - well, 8 months old - and worked fine in another vehicle with no draw. It is not dirty or corroded.

Thanks for the tips on component elimination. I don't have an amp draw clamp - but the test light idea should work.

[justimpact]

you can also use your multi meter. but set it on milli amps connect one end to the center of the negative battery terminal and the other to the negative cable keep bolth connected while removing the clamp from battery post or you may not be able to read the draw properly another thing to rember if equipt to turn off the door ajar sw. and you may need to remove the hood light and even let the processor shut down or go to (sleep) after performing these steeps you should move on to pulling fuses and you may need to have some one who can help read the meeter

[ChevyKev]

:lol: you think I work on things new enough to have "door ajar" or "processors" :tease:

Seriously though, thanks for the info. :D

[akdsmer]

:lol: you think I work on things new enough to have "door ajar" or "processors" :tease:

Seriously though, thanks for the info. :D

That's why I gave you the test light option....every hack has a test-light. :D

[ziggy]

That's why I gave you the test light option....every hack has a test-light. :D:D