lights flickering on accent

When the car is running all lights interior and exterior flicker on
the car.
When I unhook the battery, this stops.
Lights will run on just the alternator alone fine...also fine when on
the battery alone (car not running)
When car is started...with the battery hooked up...everything
flickers.

Thanks for the help.

Kathy

 

Reply to message from "Humanvirus" <> (Sat, 27 Jan 2007
10:27:27) about "lights flickering on accent":

H> When the car is running all lights interior and exterior flicker on the
H> car. When I unhook the battery, this stops. Lights will run on just the
H> alternator alone fine...also fine when on the battery alone (car not
H> running) When car is started...with the battery hooked up...everything
H> flickers.

Does this happen then you rev. the car? How old is the battery?

Best Regards
Wayne Moses <> Sat, 27 Jan 2007 14:06:10 -0600

=== Posted with Qusnetsoft NewsReader 3.3

 

Battery is a few months old...so is the alternator
I do not think it is a battery or Alternator issue...runs fine on each
one...just not both.

 

So the engine is running without the battery? Keep on doing this and
your problem will be solved, the flickering will stop.
I have always understood that electrical spikes will kill the
electronics rather quickly with the battery unhooked.

Rob

 

Reply to message from "Humanvirus" <> (Sat, 27 Jan 2007
16:25:48) about "Re: lights flickering on accent":

H> Battery is a few months old...so is the alternator I do not think it is
H> a battery or Alternator issue...runs fine on each one...just not both.


Kathy

You did not answer my first question.

I take it the battery was fully charged when new and so if not the
alternator that do you suspect?

Best Regards
Wayne Moses <> Sat, 27 Jan 2007 18:57:28 -0600

=== Posted with Qusnetsoft NewsReader 3.3

 

Battery is fine...alternator is fine (I think).
Battery passes a load test...always starts the car...has 10.8 volts
when sitting overnight...14.5 volts when car is running (Alt)
Thinking computer, bad ground, some kind of regulator...that is bad
I left the lights on to discharge the battery...car started 4 hours
later with no boost...battery is fine.
Alternator runs the car fine without the battery connected...turn on
heater, defrost, wipers and lights and horn and stereo...alt puts out
a constant 14.5 volts...no pulsing of the lights...hook up the
battery...lights flicker (pulse)...approximately 2 pulses per
second...it does this constantly as ling as the car is running with
the battery hooked up.
Reving the car has no effect on the pulsing of the lights

 

Your alternator is having problems keeping proper voltage. This could
be due to a problem in the alternator itself or a problem with the
battery capacitance.

If you’ve got another battery you can stuff in the car (even if it
doesn’t fit well) just for comparison, you should probably do that
first. If it cures the issue, replace the battery with one that fits
properly. I suspect, however, that the problem is with the voltage
regulator in the alternator. If the substitute battery doesn’t solve
the problem, you’ll need to replace the alternator

 

That is not a fine battery. You may have a short which is draining the
batter overnight. 10.8v is not the sign of good/normal conditions. I
suggest you seek out what is causing this first.

I'm having a hard time with the scenario you put together. You stated that
the battery is at 10.8v after sitting overnight, then you describe a battery
that recovers from a drain to start the car just fine. One of those
conditions can't exist in the presence of the other. At 10.8v your car
would not be turning over and starting just fine. In fact, it would likely
have troubles starting at all.

Definitely weird, but I think I would start with the battery - despite your
clear objection to that.

 

Here I am replying to my own post - sheeze! Anyway - another thought hit
me. Back in the day of mechanical voltage regulators it used to be a lot
more common to see this kind of pulsing when regulators were failing. It's
not as common today, but the principles behind it remain the same. To
boot - that could be the source of the drain that is taking your battery
down overnight. I'd have that alternator checked out with a load test.

 

Was doing it since before the alternator failed in Oct...replaced the
alt...still did it...replaced the battery...still doing it...car runs
fine...I measured the battery in my truck, my wifes sonata and the
accent...all are at 10.4 to 10.9 volt range...btw..it is -20C or -4F
here over the past few days (normal temps)...this problem has been
doing this since October...does not affect the cars performance.

 

10.9 volts without the engine running is pretty low for a fully charged
battery even at that temp. I am thinking along the lines of a hard shorted
cell in the battery. That would account for the ability to start the car, as
well as the low voltage when off. Does the voltage nosedive immediately
after shutting off the car after it's run for a while (battery should then
be much warmer than ambient). If so, you have a bad battery.

If the battery isn't bad, it may be that the vehicle never has a chance to
fully charge the battery, which could account for the flickering. Try
putting an external charger on the battery until it is fully charged. Then
drive the car. Here, wallly world has Vector brand (they say Black and
Decker) intelligent chargers for around $40. The one I bought does seem to
do a good job of charging and maintaining the batteries I've put it on. It
will also tell you if the battery is toast.