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Battery Running Down, But "Everything" Off

Hello:

Have a '84 Toyota Cressida Waggon as sort of a backup car. Hardly ever used.

Put in a brand new battery, and find it runs down after about a week or two just sitting around. Also have a new alternator.

Had the battery recharged, and find the same thing still happening.

Per the advice I was given here, I put an ammeter in series with the battery.

Find it draws about 1/4 amp.

Ignition is off This is with it just sitting in the driveway, with everything apparently off. No lights Removed the fuse for the automatic radio aerial, just in case it was stuck. No interior lights. Radio off.

I would think if it was a dead short of some wire to ground, it would be drawing much more current.

Are there any diodes that mighjt be blown, or... ?

Any thoughts on what might (likely) be the problem, or what else to check would be greatly appreciated.

Thanks, Bob

Reply to
Robert11
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.25 amps just sitting?......hmmmmm watching the meter, you should pull fuses one at a time notiong which one(s) make that go down, then go after those items specifically. I dont know that particular car, but it seems high to me.

Somewhere in the range of .05-.1 maybe..but not .25

Something in the charging circuitry could be leaking back like you suspect , but you'll need to pull things one at a time to narrow your choices down. Start with the radio fuse to eliminate that right off the bat. Be careful not to mix up your fuses while your doing all that.

Someone who knows your car may know more if that .25 is normal or not but doesnt sound like it to me.

Also, be careful with your meter and dont turn anything on with the meter in the line. You'll blow a fuse in your meter!!!

my .02

Reply to
ed

Half an amp just sounds so... bulbish. Too little for a short, too much for the idle current of those never-quite-off digital gizmos.

Sure you don't have a plunger- or mercury-switch-actuated light bulb somewhere in the interior -- perhaps one that you haven't spotted because the assembly has fallen out of its hole and is dangling

*behind* an ashtray or glove compartment somewhere?

--Joe

Reply to
Ad absurdum per aspera

That may be normal for that age car. Got a clock? Any added gadgets? In those days electrical components used power. Check by pulling fuses as mentioned but the best option is either disconnect battery or start it up every couple days....

Reply to
Woody

Okay, this is good. This is the logical first step.

Okay, this is a good second step. Now keep removing more fuses. Remove each one in turn, until it stops drawing current. Now you'll know what circuit the leaking device is on.

Probably, but first find out WHAT is leaking, then you can figure out why.

--scott

Reply to
Scott Dorsey

Why the shotgun approach? That'll take forever. Try this instead:

Pull every single fuse in the interior fuse compartment. Still drawing

1/4 amp? Then the problem is elsewhere. Not drawing 1/4 amp? Then it's one of those fuses.

Assuming 1/4 amp drain stopped with pulling all the interior fuses: reinstall 1/2 of them. See if it was in that half. Otherwise, reinstall the other half. You should be able to narrow it down in 5 iterations instead of 30. If pulling all of them didn't stop the 1/4 amp drain, then get out an electrical schematic and see where the 12V unswitched goes; probably just the starter and alternator. The alternator is more likely, so unplug that; drain gone?

You get the drift, hopefully.

Reply to
AZ Nomad

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