weird electrical problem

91White-T · Post by **91White-T** » Mon May 05, 2003 1:21 am

My battery keeps getting drained and I have no clue why... I'm on the 3rd alternator since I got the car, and tried a couple of different batteries but nothing helps. Last night it wouldn't crank, so I got it jumped and drove it home, and this morning it started right up... Also, when I put the charger on the battery, it doesnt take more than 5 minutes to recharge it to full, I am completely out of ideas on this...

Post by **Legacy777** » Mon May 05, 2003 1:28 pm

Well if the battery has been drained several times....it's pretty much toast. You will need a new one.

What I would suggest is either pulling the neg side of the battery off until you find a short, so you can still start the car.

As for finding the short, that can be a lot more daunting. First thing i would probably try to do is pull out individual fuses and see if that makes any difference, and possibly try to trace it down like that.

Shorts are a pain in the butt.

magicmike · Post by **magicmike** » Mon May 05, 2003 1:53 pm

I agree with legacy777, there must be a short somewhere. With regard to the fuses, you should get a multimeter and set it to read AMPS. normally a multimeter will only read like 10 to 15 amps of draw before it will blow the fuse inside the multimeter but you should be ok. heres what you do.

1. Set the multimeter to DC amps.
2. Disconect the negative batt terminal.
3. Place one probe on the batt. and the other probe on the disconnected cable. (basically you have the meter in series with the batt and the negative teminal.)

Now, with the car off and you should not see any draw (amps) being displayed. you might see like 1 or something or 0.5 that will be the computer. if you see like 10 or 20 or something like that, go through your fuse box and pull out one fuse at a time everytime checking the multimeter to see when the number drops, when it does you have narrowed down the problem. From there you just have to trouble shoot everything that is fused on that circuit.

Good luck,

Mike

91White-T · Post by **91White-T** » Mon May 05, 2003 3:13 pm

Thanks for the help guys, looks like I got a lot of work to do...

vrg3 · Post by **vrg3** » Mon May 05, 2003 3:43 pm

I had this problem a few months ago. In my case it turned out to be the ignition relay sticking; sometimes it would leave the ECU and sensors powered when the car was off. It's not uncommon for that relay to go bad after 10 years or so.

It's easier to replace than its location might suggest (it's on the inside of the firewall, way up under the dash).

Just to check, do you have any special aftermarket accessories? Alarm systems and stereo/amplifier setups can cause excessive parasitic load.

91White-T · Post by **91White-T** » Mon May 05, 2003 7:00 pm

All I've got are my A/F gauge and light for the boost gauge, also have fog lights but I hardly ever use em.
How can I tell if it's that ignition relay?

magicmike · Post by **magicmike** » Mon May 05, 2003 7:32 pm

Find the relay and pull it out. preferably with the meter connected like I descibed in my earlier post.

Mike

vrg3 · Post by **vrg3** » Mon May 05, 2003 7:59 pm

It'd be quicker to pull SBF-4. SBF-4 feeds the ignition relay and little else, I believe.

It's a pretty quick check to just check all the fuses.

Disconnect the cable from the negative terminal of the battery. Put an ammeter rated to at least 10 amps (many handheld digital multimeters have a range appropriate for this) between the battery and the cable. Make sure they're rigidly held in place with alligator clips or somesuch.

A properly working car, with the ignition off and all doors closed, will have a maximum of about 40 milliamps drawn.

Hopefully you'll find a much larger draw. I found 3 to 5 amps. So now, have a buddy watch the meter. Go to the interior fuse box (near the dead pedal) and pull each fuse out, one by one. Make sure you know how to put them back (the cover for the fuse box should have a little diagram for it). If you pull one and the current draw drops to 40 milliamps or less, you've found the circuit responsible for the drain.

If you pull all the interior fuses and still find nothing, go to the fuse box under the hood (between the windshield washer fluid reservoir and the battery), and do the same.

If you pull all interior and underhood fuses and there's still a draw, that's a big problem... As far as I recall, the only circuit that doesn't go through a fuse is the starter.

Once you've found the faulty circuit, you could just pull the fuse and not use it if it's not critical, or you could trace through the circuit until you find the short. Post again if you want more help on that after you have more info.

If you don't find a drain at all when you first hook up the ammeter, it's more likely that you have some kind of charging system problem or just a bad battery. After a battery goes flat, the right way to recharge it is an overnight trickle charge; simply driving the car for half an hour will usually work okay but isn't ideal.

Oh, and if you hook up the ammeter and it reads no current at all, the fuse inside the ammeter is probably blown. That happens a lot. And, make sure you turn off the dome light an dany door lights when you're doing this; that light itself probably draws a third of an amp or so.[/img]

91White-T · Post by **91White-T** » Mon May 05, 2003 11:44 pm

Ok, I just tried hooking up the ammeter and found at most 0.01 amp draw with everything off. The ammeter is working fine, the draw goes up when I turn stuff on...

vrg3 · Post by **vrg3** » Mon May 05, 2003 11:54 pm

D'oh.

Okay, so there are two possibilities -- that it's an intermittent problem or that your charging system is faulty.

My problem was indeed intermittent. My brother and I left the ammeter hooked up for about four or five hours and saw it switch between less than a milliamp and 5 amps many times. In my particular case, you could also hear the pressure exchange solenoid click whenever it changed, because the ECU was turning it on when it powered up.

You might try the exercise again at another time under different conditions.

In the meantime, I'd suggest doing what I did before I solved the problem -- put a 10mm wrench on your keychain and disconnect the negative terminal of your battery when you park. If that stops the battery from draining, you can be pretty sure your charging system is okay. It's also a theft deterrent. :)

91White-T · Post by **91White-T** » Tue May 06, 2003 2:23 am

All right, I also just checked the battery at Pep Girls and it said it was good, also the alternator is fairly new, sooo.. I'm gona leave that ammeter hooked up and see if I get an intermittent drain.

Post by **Legacy777** » Tue May 06, 2003 1:41 pm

91White-T wrote:All right, I also just checked the battery at Pep Girls....

hahahaa.....don't know why I found that so funny....but it is

chaz66 · Post by **chaz66** » Wed May 07, 2003 9:56 pm

There is a gizmo sold by harborfrieghttools that would work for you..

http://www.harborfreight.com/cpi/ctaf/D ... mber=33783

not bad for 20$ ....

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91White-T · Post by **91White-T** » Wed May 07, 2003 11:38 pm

There's no way the hood will close with that thing on the battery...lol

submannz · Post by **submannz** » Mon May 19, 2003 2:48 am

I would get an auto electritian to do a leak test to determine where and if there is a short in the wiring somewhere, because you shouldn't flog out alternators like that

91White-T · Post by **91White-T** » Mon Jun 02, 2003 6:31 pm

Update... I think I figured it out, one of the connectors on the starter was completely messed up. It was a slide on type connector and it was smashed out of shape, I replaced it and I haven't has a problem since... Unfortunately I only found this out after spending 85$ on a new starter

mile hi · Post by **mile hi** » Wed Jun 04, 2003 4:52 pm

Here's a tip on ignition relays, The relay in the Loyale series is a lot better than any relay in the Legacy. It has gold contacts rather than the silver\cadmium contacts in the later relays and it should last forever if you get one from a wrecking yard.
AL(CO)
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weird electrical problem

weird electrical problem

battery disconnect