I recently bought this car and would like some information on the operation of the alternator. The car has the DIC and when it is set on the battery charging mode it shows as low as 12.8 volts after runing about 5 minutes after starting. Is this normal? This is the newest car I have owned, and the older cars I have owned usually read higher like 13, 14 volts.

Thanks, Steve

I would say check the voltage at the alternator or battey when its running with a meter. The reading might just be wrong on the DIC.

newer cars have computer controlled alts, and step down voltage as needed to increase efficiency. your readings are normal

Thanks for both replies. I did check the running voltage with a meter and it was the same. Today it was 25 degrees outside and it was charging at 14.3 volts, so I guess it is operating correctly. This is my wife'* car and I do not drive it that often, so that is why I became alarmed.

Steve

My Digital info center is off by 1 volt when I use volt meter at battery or 12 volt acc socket. When I start the car in the am the voltage reading is highest at 14.9 volts (DIC reads 13.9) once I have run the car for a while it also drops back to about 14.3v (13.3 at DIC)
When loads are placed upon system (idle) like ac fan etc on & rear window defroster, voltage can drop by a couple of volts temporarily and readings like 11.2 (12,2 at battery) can be seen. The stock alternators are lacking in AMP department offering 45-60 AMP at idle. Quality Power can build better alts if you feel it is necessary. My Park Ave is power hungry and I now run with the best battery under the hood an Odyssey PC-1500 DT. I have no problems with my stock alt and the Odyssey even though for optimum outputs a better alt at idle would be worth the extra $ for short trips and all accessories on inside car. It takes 20 minutes plus above idle to get somewhat of a decent charge on the battery on any car. I still may buy a better alt so I can have 120 amps at idle too.
GM high output replacement performance alternators

its true the gauge isnt that accurate but the numbers he is seeing at the gauge is right for a computer controlled alt.

the newer alts are 125 but have more idle capacity. the stereo guys retrofit junk yard ones to their older cars as a cheap upgrade.

Justin, I would agree that the newer alts have the sensor wires etc but all 125 amp GM alts all still suffer from minuscule amp outputs at idle, unless smaller diameter pulley'* are used, or you buy an alternator built to 120 amp+ at idle specs.
It is simple to tell how your battery & alternators charging system it truly doing....
At night with lights shining against a wall at 25 feet back....
Turn on your wiper'* on low, your heat/fan on high, rear window defog on, stereo on and hold your brake pedal down while in park at idle....
Now step on the gas to about 1800 rpm, If your lights brighten up....at 1800 rpm and then go dimmer back down at idle, you know that your system would benefit from an improved custom built alternator.
Even with my Odyssey battery..I fail too at idle.

you have to put it together from a dozen different sites but the pre 2000 standard alt would be cs130. they were bad at idle. the post 2000 started the ad series 230 and 244 they are better at idle. 244 was the higher output. after 05 its dr44 and 44g for high output.