Load testing an Alternator

[nswst8]

With you DVOM set to 40dcv attach to battery terminals:
(RED TO POSITIVE)
(BLACK TO NEGATIVE)

Start engine: turn on lights to high beam,
wipers,
defroster,
fan to highest setting,
A/C

If volts drop below 13 volts, (is what I use as a reference)

You have a bad alternator, remember that you need at least 1/2 volt more than what you are trying to charge.

[Hauntd ca3]

dont think you meant to have the wipers on
since its load varies you'll get a funny reading

[nswst8]

Its an accumulative load, a combination of multible loads.

Then again its for the shadetree, DIYer, backyard mechanic.

Just some good info.

[AccordB20A]

cool it guess its a safer way than my alternator test whixch is to stasrt the car, disconnect neg battery terminal and if the car still runs good, then turn on headlights rear defogger blast the stereo and wind down all 4 windows at the same time

my car seemed to stall on a bass line tho.... FAIL but the battery is there to back up the alt in case of sharp peak current draws so thats my fault

[Hauntd ca3]

you'll uc an alt doin that man
an alt has to chrge into some thing or it'll fry something
the old school generaters can do that but not an alt
if you have a clamp meter attachment for your dmm you can get the output current
as well as voltage