Express Down Operation

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The express down function controls both the driver and front passenger power windows but only from the driver door power window master switch. When either the driver or front passenger window switch is momentarily depressed to the express down position, it is a direct input into the DDM. If the request was for the driver power window, the DDM supplies voltage to the power window down circuit continuously until the power window reaches the bottom of its travel. At this point, the DDM senses an over current situation on the power window down circuit and interrupts the voltage supply. If the request was for the front passenger power window, the DDM transmits a Class 2 message indicating an express down function was requested. When the PDM receives this message, the PDM supplies voltage to the power window down circuit continuously until the power window reaches the bottom of its travel. At this point, the PDM senses an over current situation on the power window down circuit and interrupts the voltage supply.