Battery draining
Printed From: the12volt.com
Forum Name: General Discussion
Forum Discription: General Mobile Electronics Questions and Answers
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=82095
Printed Date: April 27, 2024 at 3:50 PM
Topic: Battery draining
Posted By: llkillos
Subject: Battery draining
Date Posted: August 26, 2006 at 10:51 PM
I am having a battery drain problem with a 1996 Buick. I have had it to a reputable mechanic twice in the last month. The mechanic has checked the draw on the battery every hour and has found nothing unusual, so diagnoses the problem as a "bad battery." So I come home with a new battery. After a week of being parked outside (and having been driven only once) the battery is dead. It may sound strange, but when I park the car in the garage, I don't seem to have the same problem. I've had two new batteries in the last two months and am still having the problem. Any ideas?
-------------
mailman
Replies:
Posted By: killer sonata
Date Posted: August 27, 2006 at 11:33 AM
do you have anything aftermarket installed? whip out the old DMM and start testing wires when the car is off. If you have a cd player installed i would guess whomever installed it tapped into a wrong wire. same goes with an alarm/remote start.
Posted By: INSTALLER_MSS
Date Posted: September 08, 2006 at 6:20 PM
the best way to test would be to use a DMM and set it to amps setting. with the car off remove a fuse from the fuse panel and put a probe in each side that the fuse blades were in and see if there is any current draw. the only thing that should have any draw while the car is off is the radio/bcm memory which will only be about half to 1 amp max and the dome light which will be only a few amps. remove the dome light bulb and any courtesy light bulbs and eliminate that factor. try each fuse socket until you find any/all circuits with a draw and then look it up in the owners manual to see all the devices on that circuit as many devices may share the same fuse and circuit. then trial and error after that...if a circuit has a draw and there a a couple things on that circuit, unplug or unhook each device one by one and test the circuit again after each device is unplugged. if you get the same results after unplugging something, go to the next device on that circuit until the draw stops, then the last thing you unplugged leave unplugged and rehook up all the other devices and double check again. if no more current draw after you doiuble check then you found your problem. depending on the device causing it you may have a short and a defective piece. also check the alternator to see if the batts are even getting charged. there are two ways of doing this. one is to use a voltage meter or DMM and set it to volts. start the car and turn all devices off (radio, wipers, AC, etc.) the voltage should be 13.8 - 14.5 volts. another way is to start the car and unhook the positive cable from the battery. if the car dies, the alt is bad...if it stays running, its probably still good. the best way to test is to use the meter method.
-------------
"If a man made it, another can modify it...it just takes some thinking."
"If you ask questions, you're a fool for 5 minutes; if you don't, you're a fool for a lifetime."
Posted By: geepherder
Date Posted: September 08, 2006 at 9:30 PM
Your total current draw, with everything off should not be more than 50 mA.
-------------
My ex once told me I have a perfect face for radio.
Posted By: fingaz22
Date Posted: September 08, 2006 at 11:25 PM
llkillos you should always try to let everybody know what was the problem. to help others that have similar trouble. unless you still are having trouble in witch you should give use a little more info. like killer sonata asked do you or how much aftermarket equipment do you have installed? good luck bud
-------------
JUST ONE MORE AMP!!!
hu,alpine cva 1005/dva 5205
sound processor,symmetry(first one).
sub amp,power 1000 the terminator.(1992).
subs,spl comp dual 1 ohms.
punch 150hd on a 10" ev.
alotofhighs
Posted By: elicoleman
Date Posted: September 20, 2006 at 12:42 AM
INSTALLER_MSS wrote:
another way is to start the car and unhook the positive cable from the battery. if the car dies, the alt is bad...if it stays running, its probably still good.
I never heard of this. Are you sure about that. I don't mean to question your knowledge, but I used to be a mechanic and I have never heard of this before. I was always told never D/C the battery while the car is running. It can damage the PCM. As for checking battery draw, another way is to disconnect one of the battery terminals and put a test light between the battery post and cable. If it lights up, you have a draw. I use a DMM so I can make sure it is a 12V draw. Make sure all doors are closed ect, then start pulling fuses until the light goes away. From my experince, the MOST common draw in this situation was the alternator. I will work normal and test out ok, but something shorts out internally and causes a draw on the battery. ------------- 2003 GMC Yukon, Kenwood 815DVD w/ Nav. Memphis speakers. Kenwood 1200W Amp, Alpine 400W amp. Rear view camera, headrest monitors. Parrot CK3100
Posted By: bellsracer
Date Posted: September 20, 2006 at 3:32 AM
With the car off, disconnect the positive from the battery and meter the amperage draw between the battery and the cable. That will tell you if there is any draw with the car off. It should read very little draw (less than .01 amp depending on options and equipment on the Buick) If there is a draw, then start metering the fuse panels and see if there is any draw through the components of the car. I'll ask Tek to see what he knows about this thing. ------------- Never send your ducks to eagle school.
The difference between ordinary and extraordinary is that little extra.
The 3Ls of life: Learn from the Past, Live for the Present, Look to the Future.
Posted By: xtremej
Date Posted: September 20, 2006 at 12:16 PM
Disconnecting the battery while the vehicle will not damage the pcm, I have used that test many times. On newer vehicles it is easiest to just test the alternator with a dmm...Or take to an electric automotive repair shop they usually test it for free.
-------------
Posted By: supersix4
Date Posted: September 20, 2006 at 12:54 PM
To do a proper Current Draw Test, the DMM goes between the Neg(-) Battery Terminal and the Neg(-) Clamp, not the Pos(+) Terminal & Clamp. Leave the Pos(+) connections alone. Performing the test at the Pos(+) Battery Terminal will show an amperage draw, but you may not find the problem. Always go to the Neg(-) Terminal. I realize that as installers, we dislike reading manuals, but many DMM instruction manuals will show the user precisely how to perform the Draw Test. Also, in the absence of a good DMM, I have used the "Engine running, disconnect battery neg" technique to test for a bad battery and/or alternator. It worked. I've found a few defective alternators this way. Never had a PCM problem pop up, fwiw. -------------
Posted By: geepherder
Date Posted: September 20, 2006 at 2:38 PM
The problem is not actually from disconnecting the battery, but rather reconnecting it while the vehicle is running. On older cars without much electronics this is usually fine, but on newer cars, the voltage spike caused by this action can easily fry a pcm. Don't do it, plain and simple- it's like playing russian roulette with your vehicle's on board electronics. There are much better and safer ways of testing the alternator.
-------------
My ex once told me I have a perfect face for radio.
Posted By: Mad Scientists
Date Posted: September 21, 2006 at 12:46 PM
"Warning: Never disconnect a battery cable while the engine is running to "test" the alternator. Doing so can cause high voltage spikes that can damage the alternator as well as other electronics." https://www.aa1car.com/library/2003/us20310.htm Here's a more in-depth discussion of Toyota charging systems.. https://www.autoshop101.com/forms/h8.pdf#search=%22disconnecting%20battery%20to%20check%20alternator%22 **never** disconnect the battery while the engine is running.. it won't kill an electronics module every time, but how often do you need to buy one to realize it's not a good idea, and not recommended by any vehicle manufacturer? "To do a proper Current Draw Test, the DMM goes between the Neg(-) Battery Terminal and the Neg(-) Clamp, not the Pos(+) Terminal & Clamp. Leave the Pos(+) connections alone. Performing the test at the Pos(+) Battery Terminal will show an amperage draw, but you may not find the problem. Always go to the Neg(-) Terminal" Why not?.. aside from the negative terminal being safer (on a negative ground car) what difference will you see using the positive side vs. negative side? I'd think it'd be a violation of Kirchoff's Current Law? Jim
|