voltage reading

[derrik38]

i have a 1992 buick regal 3800.the voltage reading seems a little high at around 17.is this ok are what does this mean?

[MT-2500]

Originally Posted by derrik38

i have a 1992 buick regal 3800.the voltage reading seems a little high at around 17.is this ok are what does this mean?

It will fry the battery and alternator running that high.
Check the battery and cables out first.
What is the battery voltage with engine off?
A good 12 volt battery should read 13.6 volts.
Charging voltage should not be over 14.5 with every thing turned on.
If battery and cables and grounds are good and you are not trying to run one of the High FI music boxes.
Also check it with a good volt/ohm meter.
Dash gauges are not that accurate.
check out alternator.

[BNaylor]

Actually GM specs for the Delcotron CS130 charging system states that up to 16 -17? volts is acceptable but it is on the high side. If it goes beyond that then a charging system/battery fault light should illuminate on the IP. The charging system is monitored by the ECM module. Voltage regulation is performed by the internal voltage regulator built into the alternator. High alternator output may lead to premature burn out of the lamps or improper ECM operation.

On battery static voltage (engine off) I would say around 12.0 - 13.0 volts is normal on a battery with a proper charge or even a brand new one. I get typically around 12.5 volts.

[MT-2500]

Originally Posted by derrik38

i have a 1992 buick regal 3800.the voltage reading seems a little high at around 17.is this ok are what does this mean?

Here is a test from Mr. Mitchell.
http://members.troublecodes.net/crunch/92REGALALT.pdf

If you are seeing 17 volts all of the time and the battery is good shape it will end up frying the battery.
What is your charging voltage at 1500 RPM with everything turned on and battery charged up good?

[BNaylor]

I agree the reading is antenna raising high but is it an actual fault or a whacky voltage gauge at the IP.

According to the 92 Regal owner's manual his voltage readings on the IP cluster gauge should be in a range of 11- 15 volts normally. The gauge maxes out at 18 volts and the red area looks like it starts a little below 18 volts. The gauge is marked 8, 13, 18. 13 is the center of the gauge. An actual charging system fault should be accompanied by a "Check Gauges" indication on the IP.

The GM service manual specs for undercharged or overcharged battery are similar to the Mitchells MT posted. At the 1500 rpm test no load without carbon pile tester if voltage is greater than 16 volts or below the static reading of the battery with ignition to off and alternator/generator cable disconnected read with a multimeter (12.0 - 13.0 volts?) then it recommends replacing the generator/alternator. With load or the carbon pile tester you check current - amperage. Amp output must be within 15 amps of the rated output of the alternator. For a typical CS130 alternator it should be rated at 105 amps.