The following information is right out of the online 2014 6.7 CTD "diesel supplement manual" pages 199 & 200
Pretty sure my 2014 Cummins has a WTS light, but I will have to check to be sure, but the manual says I do.
NOTE: The temperature displayed in the Electronic
Vehicle Information Center (EVIC) does not necessarily
reflect the engine manifold air temperature. Refer to
“Electronic Vehicle Information Center (EVIC)” in “Understanding
Your Instrument Panel” for further information.
When engine temperatures fall below 66°F (19°C)
the “Wait To Start Light” will remain on indicating the
intake manifold heater system is active.
Follow the steps in the “Normal Starting” procedure
except
1. The “Wait To Start” telltale will remain on for a period
of time that varies depending on the engine temperature
2. While the Wait To Start” telltale is on, the EVIC will
additionally display a gauge or bar whose initial
length represents the full Wait To Start time period.
Its length will decrease until it disappears when the
Wait To Start time has elapsed.
3. After the “Wait To Start” telltale goes off, turn the
ignition switch to the START position. Do not press the
accelerator during starting.