LOW VOLTAGE and VOLTAGE SWINGS IN MY C-5
10-18-2014, 05:32 PM
#1
Heel & Toe
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LOW VOLTAGE and VOLTAGE SWINGS IN MY C-5
I have a low mileage C-5 - under 3K, with an "Optima" red top battery. As I drive, after the "DIC' shows 14 Volts, within 20 minutes, Voltage slowly decreases, and the DIC shows 13.3, or lower. Turning the engine off, the car starts easily, but the Voltage is still shown as 13.3 or under.
The Dealer tells me that alternators do not go bad often, and that a may have a weak cell in my battery, which keeps the Alternator from getting it to a full charge, and will in time cause the Alternator to fail.
Is it normal for such a Voltage drop (from 14.0 to 13.3) to occur while the car is being driven? Do Corvettes eat batteries? Yes I have hooked it up to a "Battery Tender," but this this is a drag on a virtually new car.
This is my second Optima battery - the first lasted a little over a year, was completely dead, and would not take a charge. The Battery Dealer replaced it - but said he'd do this only once.
Whenever the DIC shows Low Voltage, the car cranks very slow, but starts.
I'm hearing that the "Optima" quality has gone down, and that a "Bosch" battery might eliminate these Voltage Swings - getting a Delco battery gets an immediate - Don't buy one. Any thoughts?
Thanks
The Dealer tells me that alternators do not go bad often, and that a may have a weak cell in my battery, which keeps the Alternator from getting it to a full charge, and will in time cause the Alternator to fail.
Is it normal for such a Voltage drop (from 14.0 to 13.3) to occur while the car is being driven? Do Corvettes eat batteries? Yes I have hooked it up to a "Battery Tender," but this this is a drag on a virtually new car.
This is my second Optima battery - the first lasted a little over a year, was completely dead, and would not take a charge. The Battery Dealer replaced it - but said he'd do this only once.
Whenever the DIC shows Low Voltage, the car cranks very slow, but starts.
I'm hearing that the "Optima" quality has gone down, and that a "Bosch" battery might eliminate these Voltage Swings - getting a Delco battery gets an immediate - Don't buy one. Any thoughts?
Thanks
10-18-2014, 10:30 PM
#2
Melting Slicks
My 97 always ran from 12.9 to 13.5 and was told it was normal. I had the car for six years and it never caused a problem. As for vettes being hard on a battery well I can tell you that if mine sat for more than 3 weeks it would drain the battery down. Never did find out why but was told that alot of these cars with all these computers and such will do that. So if mine were to set for a while I would either put a tender on it or unhook the battery.
10-19-2014, 05:33 PM
#3
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Location: Anthony TX
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CI 6,7,8,9,11 Vet
St. Jude Donor '08
The volt meters in the car DO NOT display the actual battery voltage.
It shows you the foltage out of the ignition switch. That voltage can be significantly different than battery voltage depending on the condition of the contact inside the switch.
Measure the voltage at the battery and on the back of the alternator (BATT Terminal)
Compare that to the the voltmeter on the dash.
The advice given above by 8VETTE7 is spot on!
BC
It shows you the foltage out of the ignition switch. That voltage can be significantly different than battery voltage depending on the condition of the contact inside the switch.
Measure the voltage at the battery and on the back of the alternator (BATT Terminal)
Compare that to the the voltmeter on the dash.
The advice given above by 8VETTE7 is spot on!
BC