Shift Control - Grade Logic Control
WARNING: This page is about a different car, the 2013 Acura MDX, 2012 Acura MDX, 2011 Acura MDX, and 2010 Acura MDX. However, it is still accessible from the selected car via links, so may be relevant.
The grade logic control system is used to control shifting in D, and in S with automatic shift mode. The PCM compares actual driving conditions with programmed driving conditions, based on the input signal from the throttle position sensor, the engine coolant temperature sensor, the barometric pressure sensor, the brake pedal position switch signal, and the transmission range switch, to switch shifting control from the normal control to the ascending or descending control when the PCM determines that the vehicle is ascending a slope or being driven down a slope.