problem with my battery/alternator?

Question

well, i have a 92' sc400 and something has been draining my battery, i really hope i dont need a new alternator, so ive been trying to find out if there is anything else that could cause this problem. i dont think its my alternator because if i get a jump, and drive for a while, it will start right back up...but if i let it sit for a while, it goes down and wont start...ive already disconected my trunk light, and my antenna motor, just because ive read a few other problems similair to mine that were solved by that. I also recently noticed that my security light stays on when my car is off, it flashes, and i never noticed it before. could that be my proble? also while im driving my electrical stuff is most effected by the turn signals...if that helps....please help, i like my car a lot and i feel sick when it has problems...

Answer 1

First the alternator and battery should be tested "off the car" to make sure that they are both good. Assuming that they are checked and proven good then you have a short or load in the system. Easy to find in most cases as you simply put a 12 volt test light in between one battery cable and the battery. The light will light up somewhat as there is almost always a small drain on computer controlled cars as the computer, radio, etc. all have backup current draws when the car is not running. Make sure doors and such are all closed so that no light are on etc. Then pull fuses one by one from each of the fuse boxes until the light either goes out, or dims a lot. That will tell you which circuit is drawing the current. The fuse diagrams will tell you what items are on that circuit and you then know where to look for the problem. Test the alternator and battery first though as particularly the alternator as mentioned by others already can cause such a problem if not charging to right voltage and having a bad diode assembly inside. You can sometime notice this in such things as the turn signals, headlights, etc. due to lower than normal charging voltages. However shorts can cause the same effect as well so test as described above if alternator and battery are not the problem.

Answer 2

How old is your battery? ALot of people think that a car battery will last forever with simple recharging. It doesnt work that way. They only last for so long. Next. check your ground wire. the wire from your battery that grounds it to the frame of your car. Picture the electricity that leaves the battery by means of the positive cable must make a complete circle and return through the negative cable. The battery supplies the current to start your car and when the demands of your cars electrical system exceeds the output of the alternator. The alternator supplies the current when the engine is running and at the same time recharges the battery. If the belt that turns the alternator is loose or cracked it can cause the alternator to not work properly and which in turns means the battery wont be getting recharged. but since you said that it will start up after driving and wont after sitting you dont have an alternator problem. what you do have is something sucking power while the car is parked. . If you dont have the money or time to take it to get checked right now for the mean time when you park open the hood and remove the negative cable from the battery. this will stop any and all power leaks while the car is parked. If it is due to the battery being old and shot out you might want to borrow one of those quick jump portable chargers until you can afford a new battery . If you have the cash just go get it checked out.. It is better safe than sorry.

Answer 3

Well the worst thing it could possibly be is your alternator, but first check all the wiring from the alternator to the battery. Any connection leading back to the battery. Check ALL ground and snap on connections. Clean the inside of the snap on connection with a blade and WD40 to get rid of rust or moisture forming inside. You have to check every single wire, after doing this if you still have the same problem, remove the alternator and get it tested somewhere like Auto Zone. Hope this helps.

Answer 4

Disconnect battery like over night to see if problem persists. If it doesn't you have a drainfrom an electrical component. I had a problem with the brake light switch. Brake lights were not on but there was a drain to the lights from a faulty switch. Also afer disconnecting the battery touch thepositive wire to the battery post.and watch very closely for any signof a spark with ground wire to battery still connected. If you see any spark you have a drain in the electrical system.

Answer 5

your battery might be going bad haveit checked. another thing to check make sure the doors are closed, the dome light is off and anything else thatmight be on make sure it is off. disconnect the negative cable from the battery and put a volt meter between them. if you get a reading, you have something draining the battery. to try and isolate it, remove one fuse at a time and see if the voltage reading goes away. when it does that will narrow down which circuit has the problem hope this helps

Answer 6

Sounds like the battery and/or it's connections. Get a new battery at Wal Mart (45 dollars) and clean up your wire connection to the battery. Use a wire brush or steel wool and then put a light coating of grease on them before reconnecting.

Answer 7

it's your battery. if you can drive it after a jump, turn it off and back on your alt has charged the battery enough to restart it. when it sits overnight the battery loses charge from minimal pull, radio and ecm memory and using remote or electric locks. you prabably have a dead or shorted cell, take it out and test it to make sure. any major parts store will do this for free, maybe even on the car, off is better.

Answer 8

Have a Autozone/Advance Auto Parts test your battery And your alternator.

Answer 9

If you check your starter If your battery goes down and your alternator is good its the armchair in your starter is bad ,,,,,,change your starter

Answer 10

its your alternator