Circuit/System Description

The drivers shift control (DSC) also known as the Tap UP/Down feature allows the driver to shift or change gears similar to a manual transmission. Activating the DSC is accomplished by placing the shift lever in the manual (M) mode position. To place the shift lever in M position, move the shift lever to the right from the drive (D) position gate. When the shift lever is in the M position an upshift is accomplished pushing the shift lever forward. A downshift is accomplished by pulling back or pushing rearward on the shift lever. A redundant set of Tap Up/Down switches are available on the steering wheel horizontal crossbar facing the instrument panel. The plus (+) switch is located on the right side of the steering wheel and the minus (-) switch is located on the left side of the steering wheel.

The body control module (BCM) supplies and monitors the signal circuit to the Tap Up/Down switches. When a Tap Up/Down switch is activated, the BCM recognizes the voltage change on the signal circuit. The BCM sends the requested shift command on the serial data line to the transmission control module (TCM) to perform the shift.