Posted by Paul(in NY) [12.64.186.119] on Friday, May 08, 2015 at 15:13:04 :
Is it possible for a alternator to put out its rated voltage (14.7) in this case, but not have the current capability its designed for to support the OEM electrics in a vehicle ?
I have a electrical problem with my 97 Jeep Grand Cherokee, that I have not yet solved.
Under the following conditions all is well, Dash voltmeter and my digital voltmeter showing 14.7 volts;
No electrics on
Head Lights only on
Heater/AC blower only on low or medium
The problem condition shows when the following is done;
Heater/AC blower on high.
Heater/AC Blower on low or medium and head lights are on
In either of the above high current draw cases, you can watch the dash volt meter and my digital voltmeter hooked at the battery, or alternator output post, quickly drop from 14.7 to 12.1 volts, and will continue dropping if I allowed it. All dash gauges drop to zero, dash Check Gauges light comes on. Jeep continues to run, for how long, I have not tried my luck LOL.
The fix is simple, shut off the engine, turn off the blower and restart and all is well. I have cleaned and checked all battery and alternator power and grounds. Serp belt is not slipping, at least its not squealing.
So back to the original question; Is it possible for a alternator to put out its rated voltage (14.7) in this case, but not have the current capability its designed for to support the OEM electrics in a vehicle ? Blown Diode in Alternator ???
Thanks
Paul
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