jmcboost said:
jmcboost said:
edit: Sorry I wasted your time. I am sure somebody some where will show you how to hook up the leads in series.
Need advice on troubleshooting battery drain
- Thread starter jmcboost
- Start date
edit: Sorry I wasted your time. I am sure somebody some where will show you how to hook up the leads in series.
"I have a good multimeter and good wiring knowledge".
"What is the best way to hook the multimeter up to the electrical system to measure the current when the car is off? Do you have a diagram?"
"How do you test or hook up your multimeter for "perisitic" current draw"
"Did I ever say I didn't know how to use a multimeter?"
You didn't have to because it's obvious you don't. One of the most common uses of a meter and one of the simplest tests known in auto-electrical troubleshooting had to be explained to you. Nick may be blunt at times but he *was* trying to help you and his advice was/is completely valid.
"What is the best way to hook the multimeter up to the electrical system to measure the current when the car is off? Do you have a diagram?"
"How do you test or hook up your multimeter for "perisitic" current draw"
"Did I ever say I didn't know how to use a multimeter?"
You didn't have to because it's obvious you don't. One of the most common uses of a meter and one of the simplest tests known in auto-electrical troubleshooting had to be explained to you. Nick may be blunt at times but he *was* trying to help you and his advice was/is completely valid.
Sorry if I'm straying away from the current (no pun intended) conversation, but do you have an aftermarket alarm installed? I've seen those suck a battery dry before.
Josh
Josh
You guys that are not helping are beeing Jackass's. I used to read your posts all the time (Nick M and Jetjock) and I learned a bunch. Now you just want to get on here and start an arguement with me over whether I know how to use a multimeter or not. Grow up!!! Nick M. are you really 33, you act more like 13. Trying to prove to everyone that you know more than them. There is more than one way to test for current draw or a short, I am pretty sure you could test the continuity from the positive and negative leads from the car with no battery hooked up, or I could use a logic probe and test for wires shorted to ground, but what I was asking is what way do you think is best. So please, for the third time don't post unless you have some mature and helpfull info.
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JZ_killa_t68 said:
Yes I do have an aftermarket alarm, I am looking at that also, but I think I have it narrowed down to the dome light. Thanks for beeing helpfull. Apperently posting on here is sometimes a contest about who's right and not a helpfull community of Supra bretheren. :icon_bigg
I gotta agree with JMC on this one I see way to many self imolated braniacs respond to questions from young folks asking for help and knowledge. Honestly if someone posts a question on Supramania either help, answer or keep your freaken insults, bragging, and basically nothingness responses in your mind, which is where they belong anyways. Just an FYI EVERYONE LEARNED ALL THEY KNOW FROM SOMEONE ELSE.....PERIOD.
Teachers are cool, come in all flavors, sizes, and intellects.
On the battery have you positivly made sure the battery is good? the alternator is good?. One easy simple test to determine this is with the car running, disconnect the negative battery cable. If they car continues to run the alternator is good since it is generating enough electricity to run at an idle. It can also indicate a weak or bad battery since it runs at an idle but goes dead after a period of time, meaning the battery isn't taking the proper charge to keep itself charged. If it died when you removed the Negative cable the alternator is either bad or weak and can't keep the car running at an idle.
Rick
Teachers are cool, come in all flavors, sizes, and intellects.
On the battery have you positivly made sure the battery is good? the alternator is good?. One easy simple test to determine this is with the car running, disconnect the negative battery cable. If they car continues to run the alternator is good since it is generating enough electricity to run at an idle. It can also indicate a weak or bad battery since it runs at an idle but goes dead after a period of time, meaning the battery isn't taking the proper charge to keep itself charged. If it died when you removed the Negative cable the alternator is either bad or weak and can't keep the car running at an idle.
Rick
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I was only pointing out the hole he dug himself into. By doing so he came across as a fool. And you'll note I didn't respond to this thread before even though I could've easily told him all the tricks mentioned and a bunch more. Why didn't I? Because he obviously wanted his hand held. Five minutes with Google and he'd have learned all he wanted to know.
As for your "help", disconnect the negative battery cable? Lol! You gotta be kidding me! Are you actually suggesting someone do a deliberate load dump on an EFI equipped vehicle? Load dumps have the potential (pun intended) to destroy every piece of electronics in the car. If everyone learns from someone else (BS btw) learn this: he'd be a fool to listen to that advice. You'd better not quit your day job...
As for your "help", disconnect the negative battery cable? Lol! You gotta be kidding me! Are you actually suggesting someone do a deliberate load dump on an EFI equipped vehicle? Load dumps have the potential (pun intended) to destroy every piece of electronics in the car. If everyone learns from someone else (BS btw) learn this: he'd be a fool to listen to that advice. You'd better not quit your day job...
jetjock said:
This is my Supra Google!!! We all have one thing in common, the MK3 Supra, so help someone out instead of telling them not to do it, or argueing with them. Nick M and Jetjock you are both smart guys, I needed your help and I didn't get any from you.
Now that this thread is hijacked....that isn't true. You said you didn't know how to do the test, I said find somebody that does, there is no shame in paying a mechanic, and you took that personal somehow.
"One easy simple test to determine this is with the car running, disconnect the negative battery cable. If they car continues to run the alternator is good since it is generating enough electricity to run at an idle. It can also indicate a weak or bad battery since it runs at an idle but goes dead after a period of time, meaning the battery isn't taking the proper charge to keep itself charged. If it died when you removed the Negative cable the alternator is either bad or weak and can't keep the car running at an idle."
I know I'm new here and probably should just keep my mouth shut, but please don't do this. Never mind the effects it may have on electronics, it isn't a reliable test, hasn't been since the days of generators. Sometimes an old alternator will have enough residual magnetism in it's armature to generate enough current to keep an ignition system firing and sometimes it won't. Alternators need an exciting current to produce electricity.
If you want to test your alternator hook up your multimeter with the car running and look for 14-15 volts output from the alternator. Load it up with lights, blower, wipers, stereo, defrosters, etc., and see how it keeps up. (Chances are it won't keep up at idle, but it shouldn't completely fall on it's face either.)
Load testers for batteries are available quite reasonably priced.
I know I'm new here and probably should just keep my mouth shut, but please don't do this. Never mind the effects it may have on electronics, it isn't a reliable test, hasn't been since the days of generators. Sometimes an old alternator will have enough residual magnetism in it's armature to generate enough current to keep an ignition system firing and sometimes it won't. Alternators need an exciting current to produce electricity.
If you want to test your alternator hook up your multimeter with the car running and look for 14-15 volts output from the alternator. Load it up with lights, blower, wipers, stereo, defrosters, etc., and see how it keeps up. (Chances are it won't keep up at idle, but it shouldn't completely fall on it's face either.)
Load testers for batteries are available quite reasonably priced.
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well frank, thats a good solid point about alternator's
i do remember that modern computers can control the out put of an alternator by the current at the armature i belive..
the way i was taught to test a battery was to load it, should crank engine for 15 seconds and not fall below 9.6volts while cranking and return to 12.4(12.6 if new batt)
i do remember that modern computers can control the out put of an alternator by the current at the armature i belive..
the way i was taught to test a battery was to load it, should crank engine for 15 seconds and not fall below 9.6volts while cranking and return to 12.4(12.6 if new batt)
You've got to be kidding me you think electrical engineers at Toyota didn’t think people would be disconnecting the negative battery cable? Give me a break I have never Not Once ever actually seen a car damaged due to the negative cable being disconnected. It's just another stupid urban myth perpetuated by really intelligent people who heard it from some one or they read it somewhere so it must be true. I just called two friends that own auto repair shops and both said they have heard this also but have never actually seen any damage done by this method of checking. I then did a Google search and see many sites with your advice but not one said Negative cable, they all said battery cables. I believe your info is put out by those unscrupulous auto repair shops and by those that need to cover themselves as far as liability goes. Disconnecting the Positive Cable while the engine is running can and has many times led to DEATH. Just how many electrical systems have you personally damaged by disconnecting the negative on the battery? If it's zero, your repeating either what someone told you or you read somewhere. I would say it's better to give advice you have experience with than to pass on what someone told you or you read somewhere. My advice is sound and you would find it's one of the first things any shop would do when someone complains about starting and charging problems not ECU problems. Remember I said the negative not positive which could cause a surge and possibly damage something electrically. So wizards of ALL tell us all how you would go about replacing a battery if disconnecting the negative can cause damage? My cars and van have never been damaged by this method and I have personally done this a few times to check. How could it be they survived but others died? Then of course I could be wrong
Rick
Rick
suprageezer said:
Tsk tsk...load dumping = bad.
When you remove the positive connector, if you happen to be touching the metal part of connector and it happens to still be making contact with the positive terminal...you are the ground and you complete the circuit. In short...you are in a lot of pain or are possibly dead.
When you remove the negative connector, you take away the reference voltage for the battery and the load on the alternator. When you do this there is a "load dump" on the alternator. Since the alternator was energized to be running with the previous load of the battery, it still retains this energy when the load is dumped from the battery. It takes some time for the regulator insinde of the alternator to realize a load is missing and compensate for it...so the alternator's output is high for a bit.
If the output of the alternator is TOO HIGH...you can say bye bye to any electrical component in that circuit.
http://www.autoshop101.com/forms/h8.pdf
Page 9 of 21 please. This is written by the Toyota electrical engineers, not an "unscrupulous auto repair shops".
Then explain why you can and that is wrong.
Page 9 of 21 please. This is written by the Toyota electrical engineers, not an "unscrupulous auto repair shops".
Then explain why you can and that is wrong.
Something similar happened to me after I did a engine rebuild on my 87t. My battery lasted only one day. I looked for a short for weeks, pulled one fuse at a time and test for draw with a multimeter on each. Just by chance, I found that my rear defroster and mirror heaters were on constantly. So I unplugged them but never found out why it happened. Now I can't use the defroster. Or mirror heaters. But I live in Florida.
SupraDerk said:
nearly dead on. happens when you yank the neg. terminal too. think of the battery as the "load" for the alternator....remove it and voltage spikes WAY up and then the regulator steps in.
sure, all OEMs test for it (heck, that's what I DO), but did the mfg of your sweet radio test for it? probably not. did apexi test the SAFC for it? probably not. FWIW, load dump is one of the most severe electrical tests performed on vehicle electronics....