Unfortunately a continuity test will often tell you very little in a charging
circuit. I teach my students that a 'voltage drop' test of an energized or
operating circuit is preferable.
The difficulty with a continuity check is that it doesn't indicate a circuits'
ability to carry current, only that there is at least one 'strand' of wire
connected in that circuit
A voltage drop test will indicate, to a degree, the quality of the circuit.
With the battery connected, and the car running (preferably) put the RED
terminal of the DVOM ( DC volts- 20 volt setting) to the alternator output
terminal and the BLACK to the battery positive post center. The maximum
reading, with your headlights turned on should be no more than 0.5 volts (
0.1-0.3 volts is usually normal) Any higher than 0.5 volts indicates corrosion,
loose connections, frayed wires or a poor ground.
You can check the ground by putting the RED to the case of the Alternator and
the BLACK to the battery negative post. The same values apply. NEVER use the
OHM/ resistance/ continuity setting on a live circuit. :-( You will let all
the stored smoke out of your meter, and once it leaks out, the meter will no
longer perform.
This voltage drop test can be used on ANY electrical load where you suspect a
resistance problem. 'Hot' side and the ground side. Especially good on the
cranking circuit.
Hope this helps,
Damian Hall
69 2000
Stellarton Nova Scotia
>>> <nomadtrash@att.net> 06/02/00 01:38PM >>>
Check the continuity between the positive battery
terminal (disconnected) and the output on the
alternator. That will tell you if there is a good
connection between the two. Also check the ground from
the battery to the frame. Corroded or loose connections
can cause the battery to overcharge and boil. How did
you bypass the amp gauge? The connection you made there
might have come loose. I suggest running a direct power
line to the battery positive. I also suggest running a
second ground from the battery to the frame of the car.
>From experience with 100+ amp loads from car stereo
installs I have done, a second ground cable can
significantly increase the efficiency of your electrical
system. I know the little 25 amp roadster alternator
needs all the help it can get.
NT
> Started having problems last week. Went out for a drive, during which
> the battery stopped charging. Figured I'd put in a new alternator and voltage
> regulator (they weren't that expensive). Jumped the car and still not
> charging.
> What else is there in the system that could be keeping it from charging?
> Any suggestions would be greatly appreciated.
>
> Kim
> 68 2000 CSP
> NOWROC
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