Circuit/System Description
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Tow/haul mode enables the operator to achieve enhanced shift performance when towing or hauling a load. When tow/haul mode is selected, the tow/haul switch input signal to the body control module (BCM) is momentarily toggled to zero volts. This signals the control solenoid valve assembly to extend the length of time between upshifts and elevate transmission line pressure. Cycling the tow/haul switch again disables tow/haul mode and returns the transmission to a normal shift pattern. The tow/haul switch is a momentary switch and is normally open. The internal spring in the switch will always cause the switch state to return to open when not held in to the closed position.