Accelerator Pedal Position (APP) Sensors
WARNING: This page is about a different car, the 2007 Mercury Mariner and 2007 Ford Escape. However, it is still accessible from the selected car via links, so may be relevant.
The ETC strategy uses pedal position as an input to determine the driver demand.
- There are 3 pedal position sensors required for system monitoring. The APP1 has a negative slope (increasing angle, decreasing voltage) and APP2 and APP3 both have a positive slope (increasing angle, increasing voltage). During normal operation APP1 is used as the indication of pedal position by the strategy.
- There are 2 voltage reference (VREF) circuits, 2 signal return circuits, and 3 signal circuits between the PCM and APP assembly.
- 2 reference voltage circuits (5 volts)
- 2 signal return (ground) circuits
- APP1 voltage with negative voltage slope (5-0 volts)
- APP2 voltage with positive voltage slope (0-5 volts)
- APP3 voltage with positive voltage slope (0-5 volts)
- The pedal position signal is converted to pedal travel degrees (rotary angle) by the PCM. The software then converts these degrees to counts, which is the input to the torque based strategy.
- The 3 pedal position signals make sure the PCM receives a correct input even if a signal has a concern. The PCM determines if a signal is incorrect by calculating where it should be, inferred from the other signals. A value is substituted for an incorrect signal if 2 of the 3 signals are incorrect.