I'd be thinking alternator or cables. If your battery was fully charged, you would have to have a hell of a parasitic draw to drain it down that much just going into a store for a few minutes. I'd be thinking that either the battery wasn't fully charged or the cables aren't making a good connection. Are you sure that you're not able to start the rig due to battery / voltage issues and not starter issues? Does it turn over? Do the headlights work?
Got stranded at Wally World
- Thread starter WhompinFJ
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Cruiserdrew
On the way there
You are going about this wrong.
First, take out your battery and charge it with a real battery charger. It should hold 12.7-12.8 volts fully charged. Let it sit overnight-the voltage should not drop. Then take the battery for a load test at the parts store.
Install the battery and start the truck. If the battery is already full, the voltage should rise immediately to 14 volts. If it's less than 13.5, your alternator is not any good.
Shut off the car, and remove everything from the negative terminal. Then measure the Current flowing between the negative terminal and ground. That right there will tell you IF there is a parasitic draw. If there is, you need to check current in each circuit. Be methodical. Once you find the circuit, you need to look at all the components of the circuit. Eventually you will find the problem.
If I had to guess, it's your car alarm drawing down a marginal battery or, your alternator simply isn't charging.
Be careful measuring amps with your meter. Always start with amps, and if very low then switch to milliamps. THe reason is that there is minimal circuit protection and if you exceed the 400 mA with your testing it will blow a fuse inside the meter instantly.
A set of these:
http://www.amazon.com/gp/product/B001TCXOTW?psc=1&redirect=true&ref_=oh_aui_detailpage_o04_s01
is handy for finding the circuit that has the parasitic draw. Plug in the dummy fuse and measure the current between the terminals.
First, take out your battery and charge it with a real battery charger. It should hold 12.7-12.8 volts fully charged. Let it sit overnight-the voltage should not drop. Then take the battery for a load test at the parts store.
Install the battery and start the truck. If the battery is already full, the voltage should rise immediately to 14 volts. If it's less than 13.5, your alternator is not any good.
Shut off the car, and remove everything from the negative terminal. Then measure the Current flowing between the negative terminal and ground. That right there will tell you IF there is a parasitic draw. If there is, you need to check current in each circuit. Be methodical. Once you find the circuit, you need to look at all the components of the circuit. Eventually you will find the problem.
If I had to guess, it's your car alarm drawing down a marginal battery or, your alternator simply isn't charging.
Be careful measuring amps with your meter. Always start with amps, and if very low then switch to milliamps. THe reason is that there is minimal circuit protection and if you exceed the 400 mA with your testing it will blow a fuse inside the meter instantly.
A set of these:
http://www.amazon.com/gp/product/B001TCXOTW?psc=1&redirect=true&ref_=oh_aui_detailpage_o04_s01
is handy for finding the circuit that has the parasitic draw. Plug in the dummy fuse and measure the current between the terminals.
- Thread starter
- #23
What a noob mistake lol!
- Thread starter
- #24
I just got the battery load tested overnight at Oreillys and they said it was alright. So at first, output shaft told me to pull the positive wire, and you say negative. Which is it?
Cruiserdrew
On the way there
Negative is easier, both will work.
- Thread starter
- #26
I just checked the battery this morning, it's at 12.5 volts. With the car running its at 14.7. So I think the alternator is fine, before you think that's a lot it was cold and alternators are known to put out more volts when cold
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Did you also check for AC voltage just to be on a the safe side. A DC battery does not like AC voltage.
- Thread starter
- #28
Haha no I didn't check that, I don't even know what to do to check that. Any tips welcome! Honestly electrical is not my strong point it's always been intimidating to me. I've done a lot of mechanical work ever since I could basically hold a wrench. I've just been nervous messing with the electrical in a car.
Cruiser Drew has provided a solid trouble-shooting approach for this DC circuit. On top of that, if you can team up with someone local who has experience with this type of troubleshooting, then you are well on your way to learning the proper way to approach these electrical problems....and as you learn, you will reduce the uncertainty behind how electrical systems work and gain more confidence.
The thing about understanding electrical systems is that the rules are very well defined, and they are defined by the principles behind how electricity behaves. You can always count on electricity to behave on these principles...and when accidents happen it is because the human is the one who deviates from these principles.
The complexity arises because electrical circuits are designed to do different types of electrical work, so understanding both the principles behind electricity and the way that specific circuit is supposed to work is required in order to approach the troubleshooting/problem solving correctly.
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- Thread starter
- #30
Ok. I'm not home right now, but when I get home I'll be sure to test it again. Just do it the correct way this time! Thanks for the support I'll tell you guys what I find out later, and then it will be the task of fixing it!
Quick question, Nick. What do you mean by 'dead'? Did you hear the click of the starter solenoid when you turned the key in the ignition to 'START' or was it completely silent?
- Thread starter
- #32
I opened the door and the open door sensor beeped but it was really weak sounding. Then I went to start it I would turn the key and nothing, the radio wouldn't turn on, and there was no gauge lights. So the battery was almost dead, very little juice left.
Just to recap and see where you are in the trouble-shooting process:
So, according to this Voltage measurement, it appears that the battery is holding it's charge.
...and the load test indicates that the battery is good, too.
...and according to this test, the alternator seems to be charging the battery?
So then what is the next step in trouble shooting, Nick?
So, according to this Voltage measurement, it appears that the battery is holding it's charge.
...and the load test indicates that the battery is good, too.
...and according to this test, the alternator seems to be charging the battery?
So then what is the next step in trouble shooting, Nick?
Here is a really boring video comparing different battery tests (stole the link from another car blog site)...but you might give your local auto parts stores a call and see if they offer free 'Conductance' battery testing or maybe they rent the Solar 'conductance' battery tester for free?
- Thread starter
- #35
Next step is to find the parasitic drain, if I leave my car for a couple days undriven it'll be dead.
- Thread starter
- #36
Just got home time to start figuring this out, figured i would start with the current voltage. Haven't started since this morning, this just shows the draw
this morning it was at 12.5
OK. So this morning, testing the Voltage across the + and - battery terminals showed 12.5 V...and this evening it now shows 11.93 V.
Was the battery installed on the vehicle (with the battery cables attached) all day between when you saw 12.5 V this morning and 12V this evening?
Was the battery installed on the vehicle (with the battery cables attached) all day between when you saw 12.5 V this morning and 12V this evening?
- Thread starter
- #38
Yes sir. Ok so upon further checking (mainly setting my multimeter correct) this happened.
- Thread starter
- #39
Then, I decided to switch it to 2000m to see. And this happened
- Thread starter
- #40
Then I switched it to dc amperage at 200m and this is what it shows
