When I first start my 03 CTD, I notice that my lights in my truck and dash dim and if I have the heater on the fan blower lowers the speed. It will be bright then dim and then the blower will speed up and down simultaneously. I started watching the amp meter on the dash and noticed that the amps are running at about 12. After the truck warms up for 2-3 minutes it stops and the amps go back up to 15 or so and everything works fine then. Is this the sign of an alternator going out or something else?

 

This is normal, you have an intake grid heater instead of glow plugs therefor, this heater cycles on and off until the engine temperature has come up to the desired operating temperature.

 

I had the same worry after getting my truck. I called the dealer and was told this will happen every time you start your truck if the temp is under 50 F.

 

Here is what happens and how long when the grid heater cycles....

WAIT-TO-START LAMP TURN-ON TIMES
Intake temp Pre-Heat time

-40.09° F: 30.0 seconds
-20.00° F: 30.0 seconds
0.00° F: 30.0 seconds
0.09° F: 15.0 seconds
15.00° F: 15.0 seconds
15.09° F: 10.0 seconds
32.00° F: 10.0 seconds
50.00° F: 10.0 seconds
66.00° F: 10.0 seconds
66.09° F: 00.0 seconds

 

Thanks guys. I was about ready to put a new alternator on it! Thanks again.