I have a V6 Chevy S10 that eats about one battery every year or so.
It's a 2002 and I have owned it since 2004. From 2004 'till today I have
replaced the battery seven times. I've tried two different brands, Johnson
Controlls and Exide and I've always gone with the top of the line. I've gone
through and made sure the cables are tight and look to be in good shape.
I had the electrical system tested about 2 years ago by a shop that
specializes in auto electrical systems and they said the system is good.
The battery gauge always shows 14 volts, even when the battery is starting
to show signs of going bad, slow cranking starts.
The electrical is all origional, never even changed the radio or added
anything like fog lights, trailer connector or anything. It's never been in
a crash or driven hard.
Everytime it dies I have the battery tested and it always comes up bad.
I'm in Arizona and I know the desert is hard on batteries, but is it normal
to go through about one a year? This last one only lasted 9 months.
I've checked the acid levels many times and never found it low.
Do S10's normally eat batteries this quickly?
Any ideas what it could be?
Thanks for any help,
I was kind of thinking that too, but was hoping that someone else had this
problem and found a quick cure other than having to break down each
individual circuit and testing for high resistance shorts, while singling
out normal drains such as radio clock, normal seepage between contacts in
connectors and other things, broken cable strands, and failed insulation on
wires. I'm not looking forward to that kind of investagative work, but will
do it if needed.
The manager at the local Checker Auto, who is my current battery source,
said I should pull one of the cables from the battery every night and
reconnect it in the morning and see if that cures the problem. Sounds like
logical advice, but that would be a year long project, and I am hoping for a
quicker cure, though, I understand that I may not get one.
Thank you for the reply.
I do hope that someone else has other thoughts that involve less work, but I
do understand that hopes and dreams are not always consistant with reality
and I might have to face facts and travel down the longest road.
Measure the parasitic load and see what is happening. Just remove one
battery terminal and connect an appropriate VOM (on ammeter scale) in
series. If you have an ammeter that will store the maximum current during
that period it would be best. Normal parasitic drain should be in the range
of 50 milliamperes or less .
During the quiescent period, if you start showing spikes up to several
hundreds of milliamperes or even a couple of amps. then you need to do
Batteries are also sensitive to heat and vibration. You might try mounting
new battery on a rubber pad and being sure the holddown bolts are properly
tight. If you can direct a little more external air to the battery to
must be pretty high summer Arizona engine compartment temperatures, that
might also help.
During this year of battery life, do you check the electrolyte occasionally?
(I know, some batteries say they are sealed, but many can be opened to
top up with water or electrolyte)
Probably a charging/volt reg issue frying the battery, or you're
buying crap batteries.
I've had a parasitic draw on my car for years, and the batteries still
last much longer than yours.
Maybe don't drive the car as much as you though.
Car won't even start if I let it sit more than about 8-9 days.
Had the current undersized battery about a year and a half, and had
to 2 amp charge it overnight 3 or 4 times because I let it sit idle
Battery still does the job.
I'd say something wrong with your charging or crap batteries.
How are other batteries handling the heat in your location?
Not normal. I have an 02 with the original batt. in it. My 97 is on a
replacement but it also has a total of 3 batteries in it. Two matching
ones that are up front and one deep cycle that is in the rear. The back
battery runs the inverter for 110 power and for the extra lights. The
two front ones are for normal use (I do have the LEDs connected to them
when the ignition is on)
I HATE getting a call in the middle of the night and not having the
Thanks everyone for the quick replies. This weekend I will do some more
testing, taking into consideration your sugestions.
PeterD, I test the voltage across the terminals with the battery connected
and truck running, right??? I do have a Fluke 77 thats been very accruate so
I believe that Fluke has a min/max function also, so you may be able to
check for intermittent current drains. This can be a handy function.
With the engine off, you can measure the battery voltage accurately and
correlated with the temperature you can get a rough idea of the charge.
IMO this measurement is not highly indicative, but it may tell you
At 80F the voltage with the engine running should be in the range
A fully charged battery (ideally) would show a terminal voltage of
about 12.6-12.7 volts.
You might actually be running slightly "hot".
I would check the connections to the ECM first. Make sure they are
CLEAN. Also check the grounds really well. The 02 uses a signal line
from the ECM to tell the alternator what voltage to provide. The
regulator in the alternator itself doesn't control charging.
You should have one large red that connects to the battery through a
fusible link. Then on the small harness you will find a red and a gray wire.
The gray wire is the field signal to the alternator
The red wire is the sense wire to the ECM.
You should see the same voltage on the red wires and the gray wire will
change voltages as the load and temperature changes.
One thing that you can do is alter the circuit so that you can use the
I would probably throw a scan tool on there and see if the ECM is seeing
the same voltage that you see on the red wire. It could be that the ECM
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