Dash lights w/ failed alternator?

[Robert Deis]

On Wed, 4 Sep 2002, Kneale Brownson wrote:

> Deteriorating splice in the alternator-to-battery cable?

Knew you were going to say that..  I just found the splice, and there's
no visible damage, unless it's under the heat-shrink insulation- I'll jump
it again and make sure it doesn't heat up.

Still, that wouldn't explain the dash lights, would it?  All the exterior
lighting was working, as was the lighting on the radio and the window
controls-- just not the dash.


> At 07:34 PM 09/04/2002 -0500, Robert Deis wrote:
>
>
> >Patient is 86 5kTQw.
> >
> >Driving home yesterday, the little voltmeter I have hooked up to the
> >cigarette lighter varied a lot between 11.0 and 12.5 or so volts. This
> >seemed to correlate with the load on the system (i.e. whether the radiator
> >fan was on, etc) but its hard to tell for sure.
> >
> >Then without warning, the voltage began to steadily drop until it was so
> >low the sensors were giving confused readings and the car barely ran.  I
> >coasted into an auto parts store and they charged the battery for me and
> >sold me a new alternator.
> >
> >The charge in the battery got me another 6-7 miles (to my in-law's house)
> >Voltage dropped from 12.8 to 10.1 along the way.
> >
> >I swapped the alternator there and drove the 70 miles home. Voltage varied
> >between 12.8 and 12.0 along the way home, but the dash lights wouldn't
> >work.
> >
> >Went to start it this morning and the battery was dead- 2.5 volts at the
> >posts.
> >
> >Jump started it with a good battery, and everything seemed fine- dash
> >lights were working, too, and I measured 13V at the posts, and maybe 14 at
> >the alternator (crummy voltmeter..)
> >
> >Shut it off, waited for a little while, and the dash lights stopped
> >working again- any battery voltage dropped to 2.5 again.
> >
> >What's going on here?  Can you tell me where to start?
>

--
------------------------------------------------------------------------------
  Rob Deis                  "Let the people know beforehand what the law
  MiB3347                      is and what they are to expect."
  rdeis at io.com                              -- 18th Congress, Rec. 75