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Alternator/Choke issue just got worse
#1
I posted earlier about having alternator/choke issues. At the time the dash alt light would come on normally with the switch "on" then come on/go off while driving. Well, I went out to run to the store and the alt light did not come on when I started the car. Went to the store and again did not come on when the switch was turned on. Had the same high idle problem when this happened. Later that night went out to check and light came on normally and alternator was charging  around 14.6 volts to the battery.  choke worked properly. Went out this morning and dash alt light did not come on at start and alt was not charging. 12.6 volts at battery. Replaced the alternator this afternoon and light still doesn't come on with switch on and new alt not charging at battery. Any ideas?? thought this was going to be a relatively simple fix with a new alternator but given how it was acting for the last couple of weeks obviously something else is going on. Help!!
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#2
The next time you turn the key on and the alternator warning light does not come on check the "I" terminal on the voltage regulator for voltage. It should have 10 to 12 volts on it. If it does have voltage then check the "F" terminal for voltage. The "I" terminal gets it's voltage from the ignition switch, after it goes through the alternator warning light. The "F" terminal then supplies the alternator with voltage to energize the windings so the alternator can produce electricity.

If you are not getting voltage at the "I" terminal you have a wiring problem or ignition switch problem. If the alternator warning light bulb is burned out you will still get voltage to the "I" terminal through a resistor bypass.
If you are getting voltage at the "I" terminal but not at the "F" terminal the field relay in the regulator is not functioning.
If you are getting voltage at the "F" terminal the problem is either wring to the alternator, or the alternator. Remember, new does not mean good.
The "A" terminal should have voltage all the time, as it is connected to the battery. This is where the field relay and field terminal gets voltage from, after being energized by voltage at the "I" terminal.
The "S" terminal will only have voltage when the engine is running and the alternator is producing voltage.



“If you can't explain it simply, you don't understand it well enough.”
--Albert Einstein
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#3
(12-02-2018, 04:44 PM)Don C Wrote: The next time you turn the key on and the alternator warning light does not come on check the "I" terminal on the voltage regulator for voltage. It should have 10 to 12 volts on it. If it does have voltage then check the "F" terminal for voltage. The "I" terminal gets it's voltage from the ignition switch, after it goes through the alternator warning light. The "F" terminal then supplies the alternator with voltage to energize the windings so the alternator can produce electricity.

If you are not getting voltage at the "I" terminal you have a wiring problem or ignition switch problem. If the alternator warning light bulb is burned out you will still get voltage to the "I" terminal through a resistor bypass.
If you are getting voltage at the "I" terminal but not at the "F" terminal the field relay in the regulator is not functioning.
If you are getting voltage at the "F" terminal the problem is either wring to the alternator, or the alternator. Remember, new does not mean good.
The "A" terminal should have voltage all the time, as it is connected to the battery. This is where the field relay and field terminal gets voltage from, after being energized by voltage at the "I" terminal.
The "S" terminal will only have voltage when the engine is running and the alternator is producing voltage.

Thank you Don C for your help!! Apparently the voltage regulator was bad. Replaced it this morning and so far everything is functioning as it should.
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