I have a 04.5 lly ,I love the truck overall,The other day I started it up in the AM the red battery idiot light came on and the display read "Battery not charging" I do have a snowplow and the Edge, I removed both and I still had the problem,A volt meter read 12.08vdc , Drove about 15 miles,parked it for a while,did a few errands still the same then all of a sudden it cleared and the gauge was showing that it was charging. I called my local dealer with no return call,I didnt follow up since I doubt that they could simulate it, Any advice??

This appears to be a fairly common thing. My truck is doing this also. I checked the batts and they are charging. Could be the initial draw on the batt to the glow plugs. I do not get this DIC all the time.

I did find the problem last night,I went to charge it over night to get another day out of it and I noticed that under the hood there is a red battery connection point on a bracket off of the engine,I went to put on the charger to this point and I saw it ark a few times.The problem was caused by the nut needing to be tightened. I can not blame GM. It was my fault, That is where I tied in for power on the fisher snowplow. I now have used locktight.

I saw a bulletin on this not to long ago.Think it was another programming issue.

The snowplow wires should be going directly to a battery. Not to this jumpstart connection.

see this post HERE (http://dieselplace.com/forum/showthread.php?p=456745#post456745) as they are discussing the same thing.

This is the bulletin I saw.Sorry does not look like it is the same condition.

01 - 05 Chevrolet GMC Full Size Trucks with 6.6L LB7 or LLY Engines Battery Light Remains On For 30 Seconds After A Cold Start
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The following diagnosis might be helpful if the vehicle exhibits the symptom described in the PI.

Condition/Concern:
Battery or charge indicator light remains on for up to 30 seconds after a cold start and engine running.

Recommendation/Instructions:
When starting a cold engine glow plug cycle time can last 18 seconds with an after glow time of 30 seconds depending on engine temperature. After glow time of glow plugs is not indicated by the dash telltale. Average glow plug amperage draw is 130 amps. The intake air heater can use 45 amps. Due to these high current draws the battery light will remain on until the amperage draw is reduced.

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