- Jan 25, 2012
- 525
So I've been finding a few threads on this subject but no definitive answers, but I know I'm not the only one who experiences this.
One cold start I'll read around 14.7 volts, but after warming up and hitting the road the voltage will sometimes drop to around 12.5. After a little while it may come back up on it own or I can force it up by placing more load on the alternator, rear defog-headlights-fog lights-etc. On the OS I see Roadie posted that the PCM maybe doing diagnostic testing to check the battery condition. Do we know this for sure? Has anyone found anymore information regarding this brilliant GM phenomenon![Hissy-Fit :hissyfit: :hissyfit:](/forums/smilies/hissyfit.gif)
One cold start I'll read around 14.7 volts, but after warming up and hitting the road the voltage will sometimes drop to around 12.5. After a little while it may come back up on it own or I can force it up by placing more load on the alternator, rear defog-headlights-fog lights-etc. On the OS I see Roadie posted that the PCM maybe doing diagnostic testing to check the battery condition. Do we know this for sure? Has anyone found anymore information regarding this brilliant GM phenomenon
![Hissy-Fit :hissyfit: :hissyfit:](/forums/smilies/hissyfit.gif)