2008 Dodge Ram 2500 Pickup Owner Manual Diesel - Page 274

272 STARTING AND OPERATING For Extremely Cold Weather Starting - Engine Manifold Air Temperature Below 0°F (-18°C) In extremely cold weather below 0°F (-18°C) it may be beneficial to cycle the manifold heaters twice before attempting to start the engine. This can be accomplished by turning the ignition OFF for at least five seconds and then back ON after the WAIT TO START light has gone off, but before the engine is started. However, repeated cycling of the manifold heaters will result in damage to the heater elements or reduced battery voltage. Proceed by following the steps in the Normal Starting Procedure. NOTE: If multiple pre-heat cycles are used before starting, additional engine run time may be required to maintain battery state of charge at a satisfactory level. • If the engine stalls after the initial start, the ignition must be turned to the OFF position for at least five seconds and then to the ON position to recycle the manifold heaters. NOTE: Excessive white smoke and poor engine performance will result if manifold heaters are not recycled. • Heat generated by the manifold heaters dissipates rapidly in a cold engine. If more than two minutes pass between the time the WAIT TO START light goes OFF and the engine is started, recycle the manifold heaters by turning the ignition OFF for at least five seconds and then back ON. • If the vehicle is driven and vehicle speed exceeds 19 mph (31 km/h) before the manifold heater post-heat (after start) cycle is complete, the manifold heaters will shut off.