Constant drain on battery

[NismoFire]

So since I've been OTR driving, my truck has sat at home only getting cranked/ran once a week for 10-15 min. Not a big deal, I have a brand new battery (replaced in Feb). Only it IS a big deal.

In February, I was in Indianapolis at CDL school and came out of class on a <20* high day to a dead battery. I jumped it off with my jump box and drove straight to Sears. They tested it, said it was almost dead, and just replaced it. Alternator was fine. Said I probably just had a bad cell or something, so they went ahead and warrantied it.


My girlfriend got in a wreck 22 days ago, and I've been home taking care of her. I drive my truck about every other day or so. It's now 80*. Truck is hesitant to start, sounds like the battery is dead. I had to jump it at the gas station the other day. Took it to AutoZone, battery and alt tested fine. No Alternator Lights of Death.

After the great alternator debacle last year, I never hooked anything aftermarket back up to the battery (lights, CB, etc). All my interior lights are turned OFF. SES is on for p0171, but I highly doubt it's related.


Something is trickling the battery down. Even driving down the interstate at 3000+ RPM for an hour leaves it slow to start.



191k miles on odometer, 5spd w/ NA motor. I'm at a loss for ideas.

 

[TJTJ]

If driving it for an hour makes it worse, its the alternator typically killing the batteries.

The big boxes that test the alts are notorious for saying they are fine when in fact they have blown diodes or other problems they don't test for.

I found out when I had some spare alternators laying around, and I had them tested to see if they were worth rewinding...and were told they were all good...

...so I took them to an alternator/winding shop to be rewound (Higher than stock amps, etc...).

They used a MUCH better test set, and found ALL the spares were bad, and none were worth rewinding...due to stuff that the auto shops didn't test for/didn't see wrong.

The proof in the pudding is that an hour of driving charges the battery if the alternator works...and if its worse not more charged, it wasn't being charged the way its supposed to.

It could be the ground or other wire is frayed/corroded/doesn't have a good connection or continuity...and the alt ITSELF is ok...or, if wired right...then its the alt.


Just put a multimeter on the battery to see the voltage, then start it...and the voltage should go up from the alt charging it. If the alt is charging it, and the battery is good, something else is bleeding electrons...and tracking that down is next.


Go do it now...first with it all off, write down the numbers....then, start it, and get the new numbers, and write them down too...and then report back.

 

[granitex]

I would do just as TJ stated, I had an alt with a bad doide that was intermitant. The parts monkey at autozone kept saying that it was good, and that he was not going to warranty it untill I got his regional manager on the phone.

If the new Alt does not fix it start unplugging stuff like lights, and other electronic mods. After market radio setups tend to be a big source of issues.

 

[Prime]

Have similar problem. Diagnosed as a bad voltage regulator.

 

[slantyshanty]

I had similar issues not too long ago. I'm not sure exactly what fixed it because I did several things at the same time. But, over the years I have noticed many of the stock wires were corroded. We all know the stock battery terminal should be replaced as soon as you buy a gen 1/1.5 x but there are many very important wires I have replaced over the years due to corrosion. Nissan doesn't seem to use the best quality wires.

I have since replaced the main power wires coming off of the alternator to the battery and added equal gauge ground wires. The big 3+. As well as replaced the terminals. About every 3 months or so I take all of them off and clean everything. Seems to work so far.

 

[NismoFire]

If the new Alt does not fix it start unplugging stuff like lights, and other electronic mods. After market radio setups tend to be a big source of issues.

I don't have anything aftermarket hooked up. Haven't in over a year. I have a Pioneer head unit but it was plug & play.

Have similar problem. Diagnosed as a bad voltage regulator.

Interdasting. Tell me more.

I had similar issues not too long ago. I'm not sure exactly what fixed it because I did several things at the same time. But, over the years I have noticed many of the stock wires were corroded. We all know the stock battery terminal should be replaced as soon as you buy a gen 1/1.5 x but there are many very important wires I have replaced over the years due to corrosion. Nissan doesn't seem to use the best quality wires.

I have since replaced the main power wires coming off of the alternator to the battery and added equal gauge ground wires. The big 3+. As well as replaced the terminals. About every 3 months or so I take all of them off and clean everything. Seems to work so far.

I replaced the terminals after Alternator #5 I think. After that, my problems went away until now.



I'll see if I can find my voltmeter and check it. Thanks!

 

[NismoFire]

Results:

Cold (sitting for 2 days) 12.52V

Running: 14.53V

High Beams/Radio/Flashers: 14.48V

Off after all the above: 12.74V

 

[Tay-Lo]

That actually sounds good.

How old is the battery?

 

[slantyshanty]

Alt sounds good

Batt sounds bad

 

[NismoFire]

Battery replaced in February... So 3 months.

 

[NismoFire]

Bump.


Jay, what were you saying about the voltage regulator?

 

[Prime]

It's a part of the alternator. Can be replaced separately, but sometimes easier just to replace the alternator. Essentially, it ensures the voltage is correct coming out of the alt. If it fails you could get too much, to little, or anywhere in between.

 

[NismoFire]

Of course it wouldn't be a separate part. Jesus H, I'm tired of pulling the alternator out of this thing!

 

[granitex]

one of the reasons that I keep a spare in the big tool box, that lives in the trailer, with the starter,

 

[NismoFire]

Dad thinks it's the starter, since the volt readings came out well. Said the brushes could be holding the ground and causing the drain.

 

[NismoFire]

Yep, it was the starter. Swapped it out tonight. My headlights are brighter and the alternator doesn't scream near as much.

 

[Prime]

That's bizare.

 

[NismoFire]

That's bizare.

Tell me about it..my headlights have never been this bright.


What finally set us off about it-- I left my house, truck struggled to crank but it fired on the first key turn. Drove 4 miles to my parents' house. Dad walked out, I cranked it again and it wouldn't start. Put voltmeter on it, 12.58. Waited about 5 minutes and tried again. Cranked on the first key turn, probably 2nd "rotation." So I know it's not the battery..put the meter on it again while running, 14.65. Definitely not the alternator. Gotta be the starter. Took the old one out, new one hit on the first lick. I've never heard it crank like that in 3 years.


Makes me wonder if the starter had been shorting out the rest of the charging system this whole time..backing up into the battery and the alternator. Dad said something about the brushes maintaining contact or something, causing a short. The bendix worked fine, so it had to be something...or the solenoid shorting out somehow.

I also checked the grounds, and all connections were clean and secured.


OH, and the best part? The SES didn't come back on after reconnecting the battery! Ain't that some shiii...

 

[TJTJ]

Good catch then. Add that to the quiver.