Help: On my 2nd battery replacement in 6 months (1 Viewer)

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Joined
Dec 27, 2018
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Location
Auburn Alabama
Update 1: Striking through the information that was invalid or not correct from the Advanced Auto Tester. I have confirmed in a post below the true numbers (Post 13). It appears we are working with a parasitic load - unsure of how to proceed now that I have identified a circuit drawing Amps while car is at rest (10A Dome circuit is drawing 0.18A - somewhere else on the blue wire of the fusible link FL AM1 1.25B there is an additional load of 0.4-0.5A but that can't be located).

Go outside today and truck just clicks. Hit the starter with a hammer and trys to turn over but can’t. Get a jump and drive over to the parts store. Using advanced autos tester the alternator is charging and the starter is working. Battery reads bad and low voltage - charges up when running - after a minute after turning off drops again. Its an interstate group 24 battery (supposedly the one for my truck with 600 CCA - MT24). Battery test says battery puts out 450CCA after 2 months of use. Truck currently has no electrical accessories beyond a viper security system that replaced the old crappy oem one. Is it really just crappy luck and I really did get another bad battery or is there a larger issue? Help?

Edit: The battery is draining while the car is parked. Parasitic draw is in question - Alternator and battery tested good. Battery is sitting at 13.3 Volts when car is off after driving for a while. When cranking shoots up to 14.3 volts with accessories off - alternator appears to be in good shape. With load on electrical system voltage is steady at 13.74 volts.

Edit 2: I want to fully clarify the vehicle has a completely stock electrical system with minor upgrades. This is a 1993 Toyota Land Cruiser. Coming off of the battery is only one load - a relay/fuse box. That has been confirmed to be drawing 0.0A at rest. The vehicle had its crappy oem alarm removed and replaced with a viper system. There is an aftermarket stereo but the draw only occurs on the ignition circuit so no issue here. No external amps/speakers. There is no trailer harness. ABS Light is on but on an unrelated circuit to the one drawing the parasitic load. The winch that was on the vehicle has been removed for a little bit of time now. The battery should still be under warranty - but I don't intend of replacing it until the root of the issue has been solved.
 
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All I can think is parasitic load. Charge the battery then insert an amp meter between hot and + battery terminal (10 amp min setting). With everything off you should only see a very small current (clock perhaps, dome lights, stuck brake light maybe). Investigate anything bigger than a few hundred ma. Sounds like something is drawing juice with key out.
 
All I can think is parasitic load. Charge the battery then insert an amp meter between hot and + battery terminal (10 amp min setting). With everything off you should only see a very small current (clock perhaps, dome lights, stuck brake light maybe). Investigate anything bigger than a few hundred ma. Sounds like something is drawing juice with key out.
Forgive the electrically illiterate - do i need a multimeter set to 10 amps cramming it in between battery terminal and battery post to measure that for how long? How do i trace the charge? Attaching the multimeter the each individual cable coming off the battery?
 
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Search parasitic load battery test. There's some good tutorials....it basically shows if you have an abnormal draw then you go from there to try and find it.

You remove the positive cable then put the meter in-line connecting one side to the battery and one side to the now disconnected cable.
 
Excuse my ignorance, but how is a charging system that is only putting out 13.11 volts at no load "normal"?
 
Search parasitic load battery test. There's some good tutorials....it basically shows if you have an abnormal draw then you go from there to try and find it.

You remove the positive cable then put the meter in-line connecting one side to the battery and one side to the now disconnected cable.
I’ll do this, thank you.
If you have a hitch installed, check that wiring as well.
No hitch wiring installed.
 
Excuse my ignorance, but how is a charging system that is only putting out 13.11 volts at no load "normal"?
Thank you.
Your battery voltage across the terminals should be close to 14.4 VDC with the engine running. It appears that your alternator is not properly charging the battery, or there is a poor connection, or you have a dead cell in the battery dragging down system voltage.

And a automotive battery at rest that reads 12.09 VDC is depleted. A charged battery at rest will read at least 12.7 VDC.
A standard wet cell battery will not fully recover once it has been depleted.
 
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Excuse my ignorance, but how is a charging system that is only putting out 13.11 volts at no load "normal"?
Because it registers over 'minimum' for their test, if only barely. So, computer sez it's good...

I'd check the main cable connectors for corrosion - at the alternator, at both battery terminals, and body ground, and take it from there.

That battery at 8.23 Volts is toast anyways, but should be enough to hunt for a parasitic draw, either via current or resistance, and pulling fuses to isolate the circuit where a draw might occur.
 
First of all, your alternator is not working properly and so not charging the battery which eventually runs down. With the engine running, you should get in the 13.7 to 14.6 volts range. I would disconnect the battery and put a charger on it until fully charged. I would then measure the voltage, making sure it reads something reasonable (12.6 or more). I would then take off the charger and leave it disconnected for a day or two, take another voltage reading to see if it holds a charge. Hook it back up to make sure the rig starts. You could then leave it for a couple more days to see if it still reads good. If not, you have a parasitic drain along with the bad charging system. However, I have spare rigs so not having my cruiser running for a while is OK for me.
 
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Get a multimeter, you will need it for anything you're about to test.

Retest your alternator yourself: jab the multimeter ends onto the battery terminals, start the truck. Turn off lights, radio, fan. The voltage at idle should be at least like 13.7v. Try revving it to 1.5k RPM, ideally it will go over 14v. Try turning on lights, radio, fan one at a time to see how the alternator responds. The 80 has a rather weak alternator, so it might not hold up at idle very well, but if you're revving the engine it should still put out enough.

If you never get over ~13.7v at any point, it's either a corroded/loose connection, the alternator itself. Make sure the battery terminals are tight and the cables aren't loose. Take off the battery terminals and then take the cable off the alternator and clean the end of it and the alternator stud with a wire brush.

If you do get good alternator results, it's probably parasitic load. That's where something is using an abnormal amount of power while your truck is off, quickly draining it. I had it happen with the "windows always on" mod.

Does your battery have a warranty?



 
Planning on getting a multimeter today and testing multimeter on alternator after driving the truck for 30 minutes. It charges up to - number I plan to record and quickly drops. I suspect voltage drop and going to spend some time going over it and figuring out what circuit is drawing. The battery does have a warranty but I want to get it sorted out with this one before I warranty it.

Edit: battery terminals are new and tight. Battery and ground cables are all high quality new sgx wire sheathed and has tinned lugs.
 
Alright need some direction here are the updates:

After driving around town the battery is sitting at 13.32 volts with the car off.
When starting the car the voltage dips to 11.39 volts and immediately shoots up 14.3 volts with accessories (AC/Headlights) off and steadys at about 14.02 volts. With accessories on the voltage is steady at 13.74 volts at idle - at load (2k rpm held) the voltage spikes up to 14.35 volts. After turning off the car battery remains steady at about 13.3 volts.

I did the parasitic draw test and found using the 5A setting on multimeter 0.23A (I think this is mA but I don’t know). So parasitic draw exists. Using the same setting I individual probes both the engine fuse box and interior fuse box to identify a circuit that is leeching amps. Sadly all of the circuits read 0. I could get a circuit to read higher like the tail light circuit by activating the lights so I’m fairly confident the settings are right. I didn’t test the 4( I think?) large fuses - I only tested the primary fuses in the panel (ATC/Spade Fuses). Where do I go from here?

Edit: Wrong Units
 
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If you are on the 5A setting, then 0.23 will be 0.23A = 230mA which is WAY MORE than you want for parasitic. Measure the current going through each fusible link, at least you'll know which of the 3 links is carring that current.

0.23 x 24 = 5.5AH per 24 hour. You'd have a battery to flat to start the vehicle within a week or so (if the battery is already weak/damaged).

I'd also highly recommend you fully charge the battery with an actual battery charger. Alternators are meant to top up a battery, not recharge it from a drained condition.

To measure current through each fuse, you would need to remove a fuse and then insert the meter probes (with meter on amp range), obviously with doors closed etc.

cheers,
george.
 
I did the parasitic draw test and found using the 5A setting on multimeter 0.23 (I think this is mA but I don’t know. So parasitic draw exists. Using the same setting I individual probes both the engine fuse box and interior fuse box to identify a circuit that is leeching mA. Sadly all of the circuits read 0. I could get a circuit to read higher like the tail light circuit by activating the lights so I’m fairly confident the settings are right. I didn’t test the 4( I think?) large fuses - I only tested the primary fuses in the panel (ATC/Spade Fuses). Where do I go from here?

Keep the multimeter between the battery and the cable end to measure the parasitic draw. Then go around unplugging the fuses inside the truck and under the fuse panel/relay box in the engine bay. Eventually you should find one that when removed, the parasitic draw drops to acceptable levels. Mine was the window/sunroof motor relay under the hood.
 
Keep the multimeter between the battery and the cable end to measure the parasitic draw. Then go around unplugging the fuses inside the truck and under the fuse panel/relay box in the engine bay. Eventually you should find one that when removed, the parasitic draw drops to acceptable levels. Mine was the window/sunroof motor relay under the hood.
Did this - the voltage never changed removing one fuse/relay at a time from under the hood + dash + kick panel. Door was closed each time. Reading sustained 0.22-0.24. Not sure where to go here.

Edit: Voltage drop lowered when removing 10A Dome Fuse - Currently working on figuring out that circuit.

If you are on the 5A setting, then 0.23 will be 0.23A = 230mA which is WAY MORE than you want for parasitic. Measure the current going through each fusible link, at least you'll know which of the 3 links is carring that current.

0.23 x 24 = 5.5AH per 24 hour. You'd have a battery to flat to start the vehicle within a week or so (if the battery is already weak/damaged).

I'd also highly recommend you fully charge the battery with an actual battery charger. Alternators are meant to top up a battery, not recharge it from a drained condition.

To measure current through each fuse, you would need to remove a fuse and then insert the meter probes (with meter on amp range), obviously with doors closed etc.

cheers,
george.
How do I measure the current going through each fusible link considering its an all positive circle. From the circle eyelet that joins them all to the stud in the junction box? This is while the battery is connected on both position and negative? Or disconnect the negative?

Edit: I can go get an actual battery charger from Harbor Freight - How does this affect the current situation of identifying the parasitic load? I know by the end of this the battery will need to be on a proper charger.
 
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Keep the fusible link connected to battery positive, disconnect on the three other ends, and put the meter (amp setting) between each end of the links and their respective connector. Keep battery connected on the negative side as we'll
 
Keep the fusible link connected to battery positive, disconnect on the three other ends, and put the meter (amp setting) between each end of the links and their respective connector. Keep battery connected on the negative side as we'll
Well sadly I ended up doing a similar test but going about it differently. I just removed one by one each time from the positive lead to identify the problem child. This was still using the negative terminal 5A voltmeter lead to battery terminal test. I ensured all other wires in the fusible link were connected to positive terminal so confirm these readings weren’t erroneous. The plastic connector didn’t get it to zero, the black wire didnt get it to read zero, but removing just the blue wire yielded a zero reading. I looked at the loom below but couldn’t trace where it went - its thicker so guessing alternator? I just replaced the junction box/fusible link a couple months ago but to ensure bases are covered this is the condition of the blue wire. If its the alternator does this mean the power wire needs to be replaced or is the internal voltage regulator messed up?

Edit: I guess the more important question is what all is on the circuit for the blue wire?
Edit 2: Answered - Striking through unimportant.
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Additional update with information I found in another post - the blue wire looks to be FL AM1 1.25B in the following diagram that shows what's on that circuit.

Riddle me this, that entire initial chain feeds into 4 different fuses that are located under the engine bay. 15A Hazard/Horn, 10A Dome, 50A AM1, 60A ABS. This appears to be the entire initial split of the blue wire on the fusible link so these are what I need to look at. I started removing one by one and couldn't get a zero reading but I did find that the 0.23A reading drops to 0.04A when removing the 10A dome - eureka (PS the others didn't change voltage). So now I know the dome is the culprit but even removing the fuse from the circuit there is still a 0.04A reading somewhere else. I couldn't find it feeding off of the blue wire in any of those fuses and there other wires off the battery were drawing any mA off the battery. Where do I go from here after identifying the 10A dome is the issue fuse? What interior circuits are connected to it beyond just the dome lights and how do I test those components? Should I just ignore the lesser parasitic draw of 0.04A reading and chop that up as normal or "within range"?


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Edit: Not shown in photos is the removal of the 15A Hazard/Horn fuse - I can confirm without the photo there was no change in voltage load like the other 2 fuses. The only fuse removal that changed the voltage load was the 10A Dome fuse dropping the 0.23A load down to 0.04A. The other 0.04A draw hasn't been identified and I have run out of options to test leading off the blue wire (FL AM1 1.25B).
 
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Well, for low current measurements, you can move to the 200mA range to get a bit more resolution, though that meter is a super cheap piece of kit...

Something around 20mA or less is reasonably typical on a modern vehicle to keep ECU alive, radio memory alive and other 'gadgets'.

I'd move to a lower range on your meter and at some point spend a little more to get something better :). That thing looks kind of like the free junk meters that harbor freight gives away on occasion...

cheers,
george.
 

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