cmiller Posted December 7, 2008 Share Posted December 7, 2008 So I pulled to engine and changed out all of the gaskets, seals, belts, etc... last weekend. Everything went back in fine and it runs great except now the battery goes dead over night. I have a new optima battery and a 5 month old alternator in my '92 Loyale. I checked all of the connections on the battery and alternator and everything is connected. The alternator shouldn't have gone bad that fast. Any suggestions or ideas on what it could be? Thanks! Link to comment Share on other sites More sharing options...
pixO Posted December 7, 2008 Share Posted December 7, 2008 I don't have anything engine-pull specific, but you could try the pull a fuse and check each connection with a multimeter method. Whichever socket has voltage, look at the schematic for that circuit (pull the dome light bulb out). When I first got my '93 Loyale, I had the same problem with a battery drain. After checking the alternator circuit, I moved on the pull-a-fuse method and eventually traced it to the trunk. The drain was a broken ground strap for the module that sits under the third brake light. If you need schematics, I can post them Link to comment Share on other sites More sharing options...
cmiller Posted December 7, 2008 Author Share Posted December 7, 2008 Im guessing i would need to have some current running through the battery right? Need to get a charger... Link to comment Share on other sites More sharing options...
idosubaru Posted December 7, 2008 Share Posted December 7, 2008 is your alt plug brittle and nasty? not sure if that can cause a drain, but it definitely causes problems frequently. i've seen some great tips on checking for drains...and it involved what he said, pulling the fuse and finding which circuit is doing it. seems logical you'd need power for it to show. if it's a relatively benign circuit (radio for example) you might even be able to drive the car while you track down the problem without worries about a dead battery. woah - a dead optima, that's not supposed to happen! Link to comment Share on other sites More sharing options...
pixO Posted December 7, 2008 Share Posted December 7, 2008 Im guessing i would need to have some current running through the battery right? Need to get a charger... Get the battery completely charged up and then run through your tests. If you don't have a multimeter, you can get away with a test light to check voltage (though a lot of people hate them with a passion). Another option is to go down to a parts store and see if they can test the alternator on the car. Most can bench test them. I'll warn you though, I bought an alternator from schucks and I diagnosed a problem back to bad diodes and it continually tested fine on the bench. I made them exchange it and I was back in business. Link to comment Share on other sites More sharing options...
cmiller Posted December 8, 2008 Author Share Posted December 8, 2008 (edited) Man I hate electrical problems. Its so much easier to turn a wrench than to chase invisible electrical issues!!! I borrowed a charger and its charging now. So when I am pulling a fuse I am checking for a signal of current that shouldn't be there when the car is off correct? (sorry, I'm just new at electrical trouble shooting). Also I'm running out to grab a new alternator just in case. Thanks for the tips! Edited December 8, 2008 by cmiller Link to comment Share on other sites More sharing options...
pixO Posted December 8, 2008 Share Posted December 8, 2008 So when I am pulling a fuse I am checking for a signal of current that shouldn't be there when the car is off correct? Correct. You want to see what's drawing power from the battery and if the car is running, all kinds of circuits are awake. If your car is running and your alternator is working, it'll be charging the battery and working against your testing Link to comment Share on other sites More sharing options...
crockettbrat Posted December 8, 2008 Share Posted December 8, 2008 Hey there: I believe the way you do this type of test is to get a amp meter and pull the ground wire off your battery. You connect the amp meter between the neg post on your battery and the ground wire. If you have a draw it will register on your amp meter. You then proceed to pull fuses one at a time and check the amp meter with each one. When you pull the fuse for the circuit with the drain your amp meter will show no current passing thru it and you have narrowed down your search. Get a schematic and go to town. I would suggest starting on a circuit that has something thats broken. HOpe this helps and good luck. Daniel Link to comment Share on other sites More sharing options...
pixO Posted December 8, 2008 Share Posted December 8, 2008 Hey crockettbrat, that's basically what I suggested. If he doesn't have an ammeter, he can test with a multimeter. I decide to skip the "remove a battery cable and check for a draw" part because there's an obvious draw (it drains overnight, just sitting there). We've pretty much covered it, but here's a link to a generic parasitic battery test procedure: wikihow.com Remove the negative side battery cable from the negative battery terminal. Attach an ammeter(this measures amperage) 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. Check each device (circuit) on that fuse. Stop each lamp, heater, etc. to find the drain. Repeat steps 1&2 to test your repair. The ammeter will tell you exact numbers. EDITOR'S NOTE: The original author listed this repair using a 12v test light. As an ASE certified mechanic, the best place for your test light is the trash. A test light doesnt measure voltage; it shows if enough voltage is present to light the lamp. An ammeter meaures current (in amps), and that is what you are fighting against if you have a parasitic drain problem. Harbor freight sells a $3 digital multimeter (dmm) that has an amps setting. I use a Fluke, but it's whatever your trying to spend your dollars on. Link to comment Share on other sites More sharing options...
azsubaru Posted December 8, 2008 Share Posted December 8, 2008 Iis it possible that the parking light switch on top of the steering column was pushed? That'll run your battery down, and you might not notice it if you weren't out after dark. Link to comment Share on other sites More sharing options...
bheinen74 Posted December 8, 2008 Share Posted December 8, 2008 (edited) could be a bad new battery had that happen enough times, happens when you have 5 cars.- i will never buy a battery from wal mart again. got 2 bad ones there in the last 2 years. Edited December 8, 2008 by bheinen74 Link to comment Share on other sites More sharing options...
Cougar Posted December 8, 2008 Share Posted December 8, 2008 Instead of possibly spending money on a alternator that you may not need I suggest you invest in a digital multimeter. For about 40 dollars you can get a decent meter to test with and find out what the real problem is. If you do get one find a model that will handle up to 10 amps of current measurment. This will allow you to find the current draw problem you having along with checking the charging voltage. Making electrical measurements can seem a bit confusing if you aren't used to doing it but it is really an easy thing to do once you understand some basic electrical fundamentals. Purchasing a book on basic DC fundamentals will get you going on the right road. There are also good books that relate the information to automobile systems which will help you more. For much less than the price of an alternator you will have a meter and reference book that will help you understand things that you can use for the rest of your life. Once you understand these things you will truely wonder how you got by without knowing them. Link to comment Share on other sites More sharing options...
cmiller Posted December 8, 2008 Author Share Posted December 8, 2008 Well, thanks for your help everyone. After testing all of the fuseable links for drains and coming up with nothing it turned out to be the alternator spazing out. I had my receipt and took it back to Schucks in exchange for another one. Everything works great now, i just need to go through and read which code its throwing and I should be good to go. Thanks again! dancing banana for everyone! Link to comment Share on other sites More sharing options...
Cougar Posted December 13, 2008 Share Posted December 13, 2008 Thanks for the feedback and glad you got the problem solved. Link to comment Share on other sites More sharing options...
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