BigTurbo3rdGen

I have an 03 Cummins that was originally a Canadian truck and I have drove other 03's and my WTS light seemed to not be staying on for the right amount of time, it comes right on and stays on for about 4 dings the truck makes when you first turn the key and will start right up. Now the temperatures are starting to drop and when I went to start my truck the other morning it was about 42 degrees F but it is still only staying on for 4 dings and it still starts up but I know that it should stay on longer than that with it being cold because when it was 92 degrees out it was staying on for 4 dings so I know that with it being 42 degrees it should be staying on longer so what would be my issue? I have no DTC's