Intelligent Powertrain Management (IPM)
Note: IPM is standard with a DT12 transmission; IPM is not available with an Eaton or Allison transmission.
IPM is an optional fuel savings application that functions as a predictive cruise control. Using 3D digital map technology and GPS, IPM evaluates the upcoming road grade about a mile in advance to determine the best use case for most fuel-efficient vehicle speed and gear selection.
The IPM active telltale illuminates on the driver display when an IPM mode is activate. See Fig..
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1.IPM Active Telltale
Fig. 1, IPM Active Telltale, ICUC
The 3D digital map database contains profile information for over 200,000 highway miles (322,000 km) in the 48 contiguous United States, the Trans-Canada Highway, and most major Canadian highways.
Using these maps, IPM varies the cruise speed, depending on the approaching road grade.
For a vehicle equipped with the Economy Package, the default variance is +5/–4 mph(+8/–6 km/h). If the engine brake is enabled, IPM may automatically engage the engine brake at speeds higher than the cruise set speed.
Key predictive features of IPM are:
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Steep Mountain Mode — applies if the vehicle does not maintain cruise set speed while climbing. To balance travel time while saving fuel, the vehicle predictively accelerate before starting the climb, then may slow down as it approaches the crest of the hill. In this scenario the speed is allowed to fall below the cruise control underspeed.
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Crest Coasting — reduces speed before cresting a hill
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Dip Coasting — increases speed before a dip
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Predictive Shifting — selects a gear shifting strategy for upcoming terrain
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Load Balancing — maintains most efficient power for near zero road grades; small fluctuation in road speed may be seen from cruise set speed by ±1 or 2 mph
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Predictive Adaptive Cruise Control — if equipped with adaptive cruise control (ACC), allows IPM to increase following distance
Important: IPM behavior is different from that of conventional cruise control. The system incorporates features to improve the overall driver experience. Some key points to remember are:
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IPM is active only when cruise control is engaged.
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IPM only controls speed within the upper and lower bounds of the cruise set speed. The upper and lower set limits may be exceeded up to 2 mph (3 km/h) for a limited time during dip coasts, as IPM predicts the terrain demands for the most fuel-efficient performance. The driver is responsible for setting a speed appropriate for the conditions and grade. If equipped, IPM upper and lower bounds can be adjusted by selecting the quick access button on the steering wheel.
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IPM can engage eCoast sooner, later, or not at all compared to conventional cruise control.
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IPM may automatically engage the engine brake at a higher speed than the cruise set speed.
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If IPM becomes unavailable, conventional cruise control can still function.
Warning: Apply the brakes and downshift as necessary when driving on downhill grades. IPM does not adequately control vehicle speed on steep downhill grades. Failure to use normal braking techniques when IPM is active could result in personal injury and vehicle damage.
Important: IPM adjusts the vehicle set speed to achieve maximum fuel economy, but it does not account for traffic flows or surrounding vehicles.
For best fuel-savings, use cruise control whenever possible. Driver interaction with IPM is the same as standard adaptive cruise control. In the event of a problem with IPM, or when driving on a road with no profile information available, the system reverts to standard adaptive cruise control.
Using the accelerator pedal cancels the current IPM session. Disengaging the cruise control also deactivates IPM.