hi voltage warning light

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Dec 17, 2001 | 04:23 AM

stingraymarc

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hi voltage warning light

well, I posted a month ago about running my battery out while driving and I since then replaced the alternator, and all seemed fine....voltage read 15.0-15.4 during normal driving and all ran smooth for a week.

Well this morning I cranked up the 92 LT1 and she gave me the following indications:
check gauges
battery light ( charging system)
SES
and on the gauges it read hi voltage, 17.7

any idea what is happening here?

I put a meter to the battery with the engine off, read 11.8 volts
with the engine on it read 16.2-16.6 volts DC.

i can tell that the lights in the hood get brighter when I put some gas too it and get dim when I let it idle

any help is appreciated...thanks...

marc
:confused:

Dec 17, 2001 | 06:32 AM

GlockLT4

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From: Dallas TX

Re: hi voltage warning light (stingraymarc)

Since you said the battery volts was 11.x and with the engine on it was a lot higher, I'd say it's got to be something to do with the alternator... The lights getting brighter with rpm's also aims right at the alternator.

[Modified by Glock'94, 4:33 AM 12/17/2001]

Dec 17, 2001 | 07:02 AM

Shark ssn591

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From: Newport MI

Re: hi voltage warning light (Glock'94)

sounds like the alternator is failed to FULL FIELD strength, don't want to do this too long, you'll kill the electronics. Sounds like the Voltage Regulator (solid state) is bad (shop manual has a test to ground out to test max field recommends only a few seconds.)

Dec 18, 2001 | 04:42 PM

stingraymarc

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Re: hi voltage warning light (stingraymarc)

thanks to those who posted me with advice...here is the continuing situation..
after my initial discovery I went to work, then 10 hours later I come home and the battery is dead. I suspected that it was also a possibly bad battery that was fried when the original alternator went bad. replaced it today..fired her up...
still reading 17.7 so I shut her down immediately.

brought out the meter, reads 11.8 engine off..
but when fired up she read as high as 17.8-18.1, did an immediate shutdown and disconnected the battery.

obviously a bad regulator in this new alternator, but why did it take a week to fail? and what caused it? the original alternator frying the battery to make the "new " alternator work harder? I just want to know so when I swap the alternator this doesnt happen again...

thanks

Marc

Dec 18, 2001 | 06:02 PM

ShawnZR-1

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From: Canton GA

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Re: hi voltage warning light (stingraymarc)

Quote:

obviously a bad regulator in this new alternator, but why did it take a week to fail? and what caused it? the original alternator frying the battery to make the "new " alternator work harder? I just want to know so when I swap the alternator this doesnt happen again...

thanks

Marc

Why did it take a week to fail? You don't remember Ford and their regulators, do you? I think they were so bad that they installed a quick release plug on them! :) Anyway, the regulator is a couple of transistors, a couple of Zener diodes and a resistor... if the transistors or diodes are stressed too much... i.e. a dieing battery with a dead cell, more current is going to br drawn through them (beyond their rated capicity) and they'll fry. By the sounds of it, one of the Zeners went out for lunch and never came back. Blame noone on this... it happens...

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