2006 Ram 3500 w/ 5.9L Cummins, need some help on why my truck would do this.... I will drive my truck for over an hour and the Grid Heater Light will come on. Truck is running fine and at operating temperature. When light comes on, it will ding several times. Doesn't seem to run funny or turn on any other warring lights. After getting to my destination and the truck cooling down, I will start it up again and light will be on, dinging four times. I will drive another 30-40 min and the light will turn off.
This has happened to me before and the Grid Heater light will stay on. Took it to the dealer and they scanned the truck, said it was a Low Voltage code. They told me that everything was fine with the Grid Heater, but found that I had a bad fuel injector.
So now with the Grid Heater light turning on and off, I am worried that there is a bigger underlying issue.
Has anyone experienced this issue or how to trouble shoot it???

I know all about the Grid Heater Delete and that people have done that, not looking to remove it, just want to know when the Grid Heater light comes on, what does it mean and how to fix it?

Last night I cleaned the battery connections really good, not a lot of build-up but some.
Before I did this, I did the self code test. The one where you hold down the "Odometer Reset" then turn the key to "On", then release the "OD Reset". It makes the gauges go crazy and some numbers come up where the mileage read out is. However when I did this, I did get some numbers/codes to pop up, but non of them were "P" or "C" codes. Am I doing something wrong??

 

I have the same issue with the grid heater light coming on. I was at the tail end of an 8 hr drive a couple weeks ago, in warm weather and the ligth came on. Concurrent with the light coming on the car will ding about 8 times. This is an intermittent problem. I've just put in two new batteries and hoped that would correct it. No luck.

I'd also like to know the cause and the fix.

 

Slorocco,
I am not sure if I found a fix or it just stopped happening. I noticed that there was corrosion on the battery terminals, so I pulled them off and cleaned them up really well. Also noticed that one of the cables was loose, so after cleaning them I made sure they all were tight. Ever since then, I have had no issue with the Grid Heater Light coming on again. Even took a long trip to MN and back with no issue.
So I would try that and see if it helps. If it is still happening after that, I am not sure what the issue is. :/
Best of Luck.

 

Yeah, I'd read on one or two posts that old dying batteries could cause it as well. I was due for new one's so I've got two new batteries and clean connections. Problem is still there but only occasionally. Dealer said they couldn't find anything wrong.

 

PCM may need update, is code P2609 setting? Then read TSB

 

Resurrecting an old thread, sorry. Still having a problem with the grid heater light coming on. Just did a long, 5800 mile, trip around the country. The light would come on at odd times, but I did start to notice a bit of a pattern. It would often go out if I added some Howes at double the normal dosage. Sometimes even that didn't help, or it just helped for a 150 miles. It often seemed more likely to come on during a long down hill just letting the engine slow me down. It seemed more likely to happen at higher rpms like 2300 to 2400. Truck and trailer combined weight was only about 16k lbs.

As soon as I got home and un loaded it's been fine. No codes set. Brand new batteries, clean connections. What's my next step? Should I get the injectors tested?

 

At some point in time in the last 2 years, Chrysler added software to the ecm that signals the grid heater light to come on while driving if the ecm senses variations in fuel return rates (indicating injector issues). You may well be experiencing the first signs of injector failure and should probalby have them checked out by a reputable and competent diesel shop.

 

Thanks for the response. I'll do that.

 

How is the fuel filter? Been changed lately? I once ran my truck out of fuel and the grid heater light came on. After filling the truck up the light stayed on and the truck ran in a de-rated mode for about 30miles before it cleared itself.

From what others have said I think the grid light comes on when you have low fuel pressure issues.

 

this is more likely caused by a sticky fca valve