Charging issue need help ASAP

[my white eddie]

yeah, the draw thing confused me. Because I could start it after sitting
all night, but driving it seemed to discharge the battery so I said to self
"typical bad alternator symptom", besides I knew the bearings were going
out of the original one anyway. But alas still the same stinking problem.
I did pull every fuse just to find a circuit to test or at least live without a feature or two till I had time to diagnose, but even after every fuse was pulled, it still glowed like Rudolfs nose. I have devoled a bald spot on the
top of my head from "thinking" about this one.

 

[koda2000]

If this was driven at night, I venture to guess the heater and headlights flattened the battery, due to lack of recharge.

granted, driving with lights on and lots of electrical components is use would flatted the battery pretty quickly, but under in 10 mins??? and that doesn't explain the big spark when reconnecting the cable to the battery with everything off. what could be drawing that many amps and not even click a relay?

 

[my98nnj]

Alternator isn't charging, that's why your losing the batteries. As was mentioned previously in this thread. You need to check for the signal wire to the alternator. Fuse 6 under the hood is for the voltage regulator. The 11V running means the alternator isn't charging.

That's your real problem, not a short, but an open circuit to the alternator.

 

[budwich]

X2... yes your alternator may test good... BUT it has to have proper connections to cause it to "turn on and alternate"... The low voltage more than likely means a lack of voltage generation.

Go to your alternator, pull the connecting wires from it. Get a Meter and measure for voltage on each wire (to a KNOWN GROUND). You should be seeing some battery voltages on a couple of them... if not, you have a wiring issue, depending on which one isn't there (ie. A or B+).

 

[koda2000]

Alternator isn't charging, that's why your losing the batteries. As was mentioned previously in this thread. You need to check for the signal wire to the alternator. Fuse 6 under the hood is for the voltage regulator. The 11V running means the alternator isn't charging.

That's your real problem, not a short, but an open circuit to the alternator.

yeah, i'm still liking this original theory too. just because the alternators tested good in AZ's machine doesn't mean they're charging in the truck, however the OP said he checked the fuses and i believe he also said he's getting the "big battery spark" even with the alternator unplugged. but, check the signal wire by all means. i don't think i agree with the "alt can't keep up statement".

 

[Kevlar7R]

or it's generating, but not getting to the battery. Test for voltage at the alternator!

 

[koda2000]

or it's generating, but not getting to the battery. Test for voltage at the alternator!

i think the OP said he's done that and it wasn't putting out. showed battery voltage.

 

[llamaking122]

Test for the voltage at the alt like discussed. But for that amount of time it takes it may just be extra insurance to have them load test it at auto zone. just because its new/reman doesnt mean its good. Start with the basics then get into the more complex stuff. also look for corrosion on the wires etc.

 

[koda2000]

Test for the voltage at the alt like discussed. But for that amount of time it takes it may just be extra insurance to have them load test it at auto zone. just because its new/reman doesnt mean its good. Start with the basics then get into the more complex stuff. also look for corrosion on the wires etc.

OP has had AZ test the alt(s) in their test machine. if the machine says its good, it's good. the machine performs multiple tests on the alt and is very accurate. i used one for years and never had it give a false GOOD reading, but if the customer insisted, i'd exchange the alt for them and invariably the next time i saw them they'd tell me they found the real problem (usually related to wiring).

edit: i just saw where the OP says it starts after sitting all night, but is dying when driving a short while. maybe it's a combination of a bad/weak battery and an alt that's not charging because it's not getting the signal to turn on???

 

[Kevlar7R]

i think the OP said he's done that and it wasn't putting out. showed battery voltage.

I read it as he was testing at the battery.

How old is this battery?

 

[llamaking122]

Ive had 2 alts test good at auto zone yet were bad both times i think it was operator error. One time the first time it tested bad then goodo then bad. Thats why i take it to a good shop that rebuilds them now

 

[koda2000]

Went out for a smoke and checked again. no draw when sitting. No difference in running voltage with LOM unplugged (good, I guess) Voltage at alt post with it running is 10.95 steady for a while then jumps all over the place, some times as low as 3.41 V. So Iguess Ill try another quality alternator from "the Zone".

no, he also checked voltage at the alt.

 

[my white eddie]

batterys are both about 2-2 1/2 yrs old. Both show a fast "recovery
rate" after they have been disconnected from the vehicle. I suppose
I could have more than 1 issue here, but it ssems odd that both the
old and new(reamn) alternator would test good, but be bad. As far
as checking output voltage it showed less at the alternator post
than at the battery terminal with the vehicle running(???????) and
even with the alternator unhooked it was still draining. I'm thinking
that there is a bare or loose wire somewhere that is intermitently
shorting out, due to the fact it did not discharge over night the first
couple nights, but it is sucking batteries like a vampire now. I will
have more info after I can get out of work tonight.

 

[koda2000]

a battery that's that flat should not show a quick recovery rate. if recharging in the AZ machine you should be looking at about an hour to fully charge. on a medium quality home charger (say 15 amp rate) you'd be looking at many hours to fully recharge.

 

[llamaking122]

What kind of battery? If its a optima you need to charge on a trickle charger.

 

[my white eddie]

Nope they are both Duralast red tops. I always trickle charge batteries
of any kind, anyway. I just happened to have mine at work for the
office lawn tractor, so I charged them while I was working all day.

 

[Kevlar7R]

no, he also checked voltage at the alt.

Oops! You're right! My bad.

so now he needs to trace out the wires that lead to the alternator.

I kinda doubt these batteries are getting fully recharged. Need Need to figure out why the alternator isn't running. When it's doing this discharge thing you're talking about, how hot are the battery terminals? If it was truly pulling that much current they would be more then hot enough to burn your skin. If you can touch them while this is running, then i dont think there is the load you think there is.

Should be able to cheat it, and use a clip lead to put 12v on the alternator signal wire, that will answer the question of if it's the alternator, The signal to the alternator, or some other wiring problem. I dont remember the wiring off hand though, so can't tell you which one. Maybe someone else knows the wiring?

 

[my white eddie]

just had a co-worker run me and my fully trickle charged battery up to
my ride. Put in battery, sparked like a mo fo! I put volt meter across
the battery terminals(hooked up) and you could watch the voltage drop.
disconnected battery and put meter across terminals and you could see it recovering. I did make the 5 mile trip, but it is still discharging. I put the other charged battery in and checked its voltage (12.64) started it
and re-checked alternator post it showed 11.95?. I also did the amp
draw test as recommended and it showed an 8.2 amp draw with the key in my pocket and the doors closed and hood light bulb pulled. I,ll do more
in depth testing when I get done tonight as I was only out for a quick
smoke break.I'm at the point where i'm thinking bare or loose wire causing
an intermittent short, but we will see.And I will let you all know the
outcome.

 

[llamaking122]

You're losing volts between the alt and battery check grounds too. make sure the wire on the back of the alt is on too. ive left that off on accident before lol.

 

[llamaking122]

just re read that sounds like the alt isnt charging at all. its either the alt. signal wire. bad ground (i dont remember if its the ecu that controls the alt on there)