89 Accord Batt Light (Please Help!)

Ok, I am here seeking technical help in diagnosing a specific problem
with the charging system in my car.

I have an 89 Honda Accord DX, carbureted.

My battery light has been coming on intermittently. This weekend, I
installed a new battery, a new alternator and a new fuel pump. This
morning I was driving to work. At one point, the light flashed on and
off with the blinker light. Eventually it stayed on. If I turned off
all the accessories, then it would go out, until I got closer to work,
then it stayed on. I noticed all my lights were dimming, like the
battery was being drained. After I arrived to my parking spot, I shut
it off, and tried to restart it. It would not start, barely cranking
over...

So, my if battery is new and the alternator is new, why would my
battery be dead after a short (20 minute) drive to work? Is there
something I am missing here?

 

Sounds like a wiring short of some kind. Either that or one of the
devices on that chain is shorting/grounding out. Being the blinker
was involved a bit, it could even be in the wiring in the steering
column, or thereabouts. I'd do all the tests I listed in an earlier
post, and if still no good, you will have to do current draw tests
to see where the drain is. Something is shorting together, or
grounding out. That draws a lot of current and will knock a
battery down fast.
MK

 

where did you get the replacement alternator? Certain vendors have issues
with bad diodes and faulty brush installations. Sometimes your 'new'
alternator is simply bench tested with only the apparent bad parts being
replaced.

Is the belt tightened to specification? Did you install a new belt? This
failure could be caused by a silent slip of the belt.

t

 

blinker relays won't function properly if there is not a full 12volts coming
to them. They get sticky and function erractically.

You could test for phantom current draw, remove the positive battery cable
and measure Milliamps of current between the battery post and the cable.
Should be below 0.1 A.

t

 

I got the replacement alternator at Autozone. I certainly hope they
don't sell bad parts. I have never had a problem with them before.

The belt is indeed tight, I did not install a new belt. I am thinking
I have a shorted out component somewhere.

 

The first thing I would check is all connections, especially the often
neglected ground strap. Next I would suspect a possibly faulty alternator
(they are sometimes bad right out of the box).

Could be a intermittent or lower amperage draw/short elsewhere in the wiring
as well.

 

what is the voltage across the battery terminals at idle?

 

Check out this link for steps for testing your electrical system. Most can be
done with any simple digital multimeter.

http://assets.fluke.com/appnotes/automotive/beatbook.pdf