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Hello I would be willing to assist you if you like?
could you tell me how to test a basic 12v alternator with an ohm meter , i have established that it is not working by replacing it
need to know how to decide if v reg is faulty or brush/windings are the problem
Sure thing set your meter to Ohms
Test a fuse to make sure the meter is reading properly, should be 1-3 ohms
Is there a AC setting on your meter?
Okay set the meter to DC 20V if you can and place one probe on the positive terminal of the car's batter and one probe on the car's negative terminal of the battery while running.
A normal charging reading would be between 12.6-14.1Volts
anything below that and you may have a bad battery or there is high impedence ( resistance) in the battery cables, possibly due to corrossion.
ok i have no v at the alternator
Is the car runnig?
the battery is 12.8
the battery is 12.8v
okay that seems about right.
i changed the alternater the other day the new one is working
If you rev the engine up you should see a change in the volatage reading. typically if you dont see the reading get abouve 13V the alternator is bad or weak.
the alternater had no output trying to work out if it is the v reg or brushs / wireing
That is the best and easiest way to test for an alternator. Have I answered your question?
Test the cables going to and from the alternator to the battery and the battery to ground on the Ohm setting, if the resistance is above 3 the cable is bad or corrodded
no the cables are 1.67 ohm , the alternator is the problem, what is the ohm reading from + output to the case of the alternator
Give me one second
Between 3-6 ohms should be standard
its showing open curkit
Where did you purchase the alternator?
it has a bosch ee14v3 9 190 067 005 v reg with brushs , brushs are ok with on grouving on the stator
at a local outlet
Well I dont think I can help you any further. It seems like you may have a defective alternator many of the ones purchased at local stores are refurbished.
what is the ohm reading for the stator
I cannot help with that Im not sure I will seek advice from another expert.
hi jim , there is an exciter wire D+
from B+ to alternator is open curcit
from B+ to alternator case is open curcit