Voltage problems
I have an 05 grand prix. I have a new belt alternator and a
good battery. Had it tested everything is good. I can not
keep the voltage up. It will go up for awhile then back down
and stay there for a long time. It doesn't matter if it is
raining out or if it is nice out. Not sure what to do next.
4 Answers
The alternator will provide current to the battery when it has been drawn down such as after you start the car. It then changes its output depending on what accessories are running like lights, radios, wipers, etc. It can fluctuate but will normally run a nominal system voltage of 13-14 volts and sometimes drop to 11-12 if you are just at idle with no items tuned on. Only be concerned if your system voltage drops below 11 volts.
What happens if I get a charging system failure
That will depend on what failed. If its the battery, and you car is running, it will continue to run from the alternator current and not restart without a jump. If it is the alternator and your car is running, it will run until the battery can no longer support the load. If it is the starter, your car will not start.
Check the negative battery cable there is 3 wires that go in it make sure they are all 3in the cable end and there is a sensor on the wire mine 06 did the same thing I changed the sensor and put all 3 wires in a new end its good now
