Alternator Voltage Bad?

January 20, 2004

My new Battery suddenly could not start car after I parked it for one day!

Is my alternator killing the batteries. I get up to 14.5Volts when the engine is running. What is the solution to stop my batteries from going back frequently? :help:

January 20, 2004

14.5volts is not overly abnormal, as long as thats with no other electrical items on, Did you record the voltage of the Battery when the car would not start????

January 20, 2004

When I left the car for about 2 weeks and disconnected the Battery led, the voltage dropped to about 10.5V. I used another Battery to start the car and put back my Battery. After running the engine for a while, my battery voltage went up to about 13V and was able to start the car. But I am afraid that if I do not unplug the terminals and use the lights at night, it might not start in the morning. :(

January 20, 2004

Have you put a trickle charger on the Battery only to see if it has a slow short? Charge at 2-10 amps. Then with engine off, put the head lights on for 30 seconds and turn off. recheck the voltage: should still be 12.6. Too much electrolyte on the Battery top can also do this [gounding across to ground. Also a weak cell or partially broken internal connectors can also do this.

Does the voltage of the alternator stay at 14.5 or does change according to the engine speed? [internal voltage regulator]

Are the Battery cables in good shape and clean without corrosion?

January 20, 2004

Tricke charger? No, i am depending on my car charger.

The voltage does not stay on 14.5V, it increases slightly when the car is relved and at a time it was down to 14.2Volts.

I have just changed the Battery connectors though I find that there are white corosion on the negative terminal which I cleaned.

Also, there are two 30A fuses on the positive terminal. I had to disable one of them sometime ago because the fuse was blowing. The car started without the fuse so I really do not know what the fuse is for, but if you have my model of camry, maybe you might know.

If the Battery is bad, my fear of replacing it is that I do not want to risk killing another Battery :crybaby: :help: