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Battery light in Pontiac Grand Am

Second: My 2000 Pontiac Grand Am has an interesting problem. When the temperature gets below about 40 degrees F, the battery light comes on. The car runs fine, and after a few minutes, when the engine warms up, the battery light goes off. The battery is an AAA battery and is about 2.5 years old. I simply can’t remember when I changed the alternator, but I think it was done in the last three years. In your collective humble opinion, should I just run to the local parts store and buy a new battery, or run to my mechanic and let him look at the whole thing?

Thank you in advance for your kind comments

Seems that after you start your car in colder temps the battery is reporting low voltage Hmm wait, no… the batt light only comes on when the alternator stops putting out voltage I believe. Some systems report low voltage with the battery light and some or most report on the condition of the “State of charge” of the alternator… A vehicle of this age is more than likely reporting on the alternator…which does need proper voltage from the battery to put out proper DC current to charge the batt.

I would begin with checking your batt connections. They must BE clean and tight…no corrosion or loose clamps… If it is a side post battery (The most hated style personally) the same applies. I would for giggles simply clean the connectors and posts and retighten everything and see how it goes. You can also monitor the battery with a voltmeter…esp when the light comes on…note the voltage. On the hated side post batteries…sometimes the plastic shrouds that encompass the batt cable ends interferes with or gets in the way of being able to tighten the cable to battery… Many times I use a razor blade to trim this outer plastic casing to allow the cable end to properly contact the battery…but thats just me and I see a lot of battery connections in my day to day.

It sounds like your batt is just able to operate…and after a start then hits a voltage that is too low to properly operate the alternator… The batt connections is the very first place to start. A volt meter wouldn’t hurt anyone either. Let us know what you find.

Time to run…I need to complete repairs on a Rolls Royce Silver Wraith II in NJ… Fun fun fun…


@Dr. Chrisq
At The Cold Temperatures Do You Notice Anything Related To Turning The Steering Wheel? Are There Any Noises Associated With Turning The Wheel Or While The Battery Light Is Illuminated Is It More Difficult To Steer?

“…should I just run to the local parts store and buy a new battery…” [?]
Many large national chain auto parts stores will check your battery and charging system for free while you wait. You may have a weak charging/battery system. I’d go to one and have it tested.


CSA is asking you about the steering and associated noised because as he correctly surmised…it could be a loose serpentine belt not driving the accessories properly …you would normally hear this as a squeal or squeaky belt sound… Good advice. At the very least …look at your battery terminals and clamps…see if they are dirty, loose or both.


The problem you describe is most likely due to a problem within the alternator. It is always a good idea to clean the battery connections when having charging issues, even if the battery clamps look okay. Don’t over tighten the connections when you reconnect them. Make sure the connections to the alternator are good and the belt is tight. If you still have the trouble then I would replace the alternator first if you decide to swap out things.

Since the battery is only 2.5 years old, between your two alternatives you posted I think you’d be money ahead to take your car to your mechanic for a proper diagnosis. Best of luck, and happy new year!