Cummins ISM engines give you the choice between an Automotive and a Variable Speed Accelerator. The accelerator determines the 'feel' of the accelerator pedal and choice should be made on vehicle configuration and your preference.
Some vehicles are equipped with a cab switch that can be used to select the desired accelerator type. The system also supports the installation of a remote accelerator pedal in specialty applications and can even deactivate the accelerator pedal under desired conditions (example: school bus door open).
The Automotive Accelerator gives the performance you are used to having with Cummins engines. With this choice, accelerator pedal position determines the engine's torque output (half accelerator position will give you 50% of the engines available torque). If the operator desires more torque to resume a constant speed while climbing a hill, they must depress the accelerator pedal. Using this accelerator type, the accelerator pedal will "feel" the same as your automobile. If the vehicle is equipped with an automatic transmission, the selection of the Automotive Accelerator type is required.
With the Variable Speed Accelerator type, the accelerator pedal position determines engine speed rather than torque output (half accelerator position will give you 50% of the engine's rated RPM). The engine will hold the desired speed under varying load conditions by changing fueling. The Variable Speed Accelerator operates in a similar manner to the "All Speed" accelerators used in the past.
Switchable Accelerator Type
Some vehicles are equipped with a switch to change the Accelerator type. If the vehicle is so equipped, you may change accelerator type with the flip of a switch. Some operators may choose to change accelerator type under specific driving conditions, but most importantly, the feature gives the vehicle flexibility. Many operations require vehicles to be driven by more than one operator. In this case, each driver can adjust the accelerator type to their preference. This increases operator comfort and satisfaction.
Some vehicles may be setup to disable the accelerator pedals (cab and remote) under desired conditions. When the condition is met the accelerator pedals will not function. The most typical application for this option is the school bus. When the bus door is open, the accelerator pedal is disabled. When the door is shut, normal function is restored.
Vehicles may be setup to disable the accelerator pedals (cab and remote) under desired conditions. The ISM engine is capable of disabling the accelerator pedal based on a switched input. There are no required programmable parameters for this feature. The OEM must correctly install the hardware and associated wiring to enable. The most typical application for this option is the school bus. When the bus door is open, a switched input alerts the control system, thus disabling the accelerator pedal.
If your vehicle is equipped with a switch for accelerator type selection, try the different accelerators under various driving conditions. Most operators have a distinct preference, but agree that the Automotive Accelerator requires more pedal interaction with better speed "control". Many operators select the automotive choice in stop-n-go driving conditions and the variable speed choice on the highway.
If the accelerator pedal stops working, the vehicle may be setup to disable the accelerator pedal under certain conditions (Accelerator Interlock). Â