If your vehicle has the DURAMAX® 6.6L diesel engine, it will have glow plugs and an air intake heater. If your vehicle has the Isuzu 6H diesel engine, it will have glow plugs and an inlet heater. If your vehicle has a Caterpillar engine, it will have an inlet heater.

The light in the center of the instrument panel will come on when the inlet heater or glow plugs are on and the ignition key is in ON/RUN.

Wait until the indicator light goes off before turning the ignition key to START.