For the past couple of mornings on my way to work as I crank my truck the voltage gauge needle moves to 11 volts and stops then the check gauges light comes on for about 4 seconds and goes off and the voltage goes to about 14. Once I start driving I can see my headlights and dash lights dim and the voltage drops to 12 or 13 and then the lights brighten back up and the voltage returns to 14-15. It will do this about 4 or 5 times then stays around 14 and the lights don't dim anymore. Is this a battery or alternator problem?

 

It's probably just your grid heaters working but youre in Alabama, Is it getting down in the 40's or lower at night?

 

When I left for work this morning (3:00 am) the truck temp read 41*. So this is normal for cold weather?

 

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I am glad for once I noticed something different and it was not something going bad! And even better I learned something new about my CTD This truck is new to me and these have been the first cold mornings I have had it so that must explain it! Thanks for your help!

 

You might have your batteries tested too... If the batteries are getting weak it might be the cause the Check Gage light coming on...

But yes the diming lights and lower voltage is normal but if it's tripping the light then start check things out a bit...

Clean the terminals and grounds..

Check the water in the battery (if not sealed)

Etc...

Just my 2 cents...