Shift Selector
The vehicle is equipped with a column type shift selector. In addition to the column shifter, another component associated with the shift selector is the internal mode switch (IMS), which is mounted internally on the selector shaft. The IMS transmits selector position information to the TCM. The IMS detects the angular position of the shift selector shaft. This position is communicated to the TCM so that certain vehicle control functions can be coordinated with the position of the shift controls. The IMS has redundant circuitry to alert the TCM in the event of a single wire or switch failure. The neutral signal output of the IMS is typically used as confirmation that the transmission is in NEUTRAL before the engine starter is engaged. The IMS is interfaced to the starter circuit.
The operator chooses the transmission range by moving the selector lever to the appropriate gate position. When properly adjusted, the shifter gates prevent inadvertent shifting between ranges, and corresponds to the internal transmission detent positions. A positive detent is provided in the transmission in order to maintain the selector shaft in the selected position.
The TCM shift calibration determines the available forward ranges for each selector position. Although specific installations vary, typical selector positions for the 1000 Series include the following:
- P - PARK
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The parking pawl is engaged. The transmission is in NEUTRAL.
- R - REVERSE
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REVERSE is selected in order to move the vehicle backward.
- N - NEUTRAL
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NEUTRAL may be used when starting the engine and for stationary operations. The TCM disables the starter switch if a range other than NEUTRAL or PARK is selected before starting the vehicle.
- D - DRIVE
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DRIVE is the highest forward range used for normal driving. The transmission shifts to first range for starting, then automatically upshifts through the ranges, as operating conditions permit, until the highest range is attained.
- M - Manual
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Manual selection of ranges is provided by moving the selector to the M - MANUAL position. A driver shift request switch has been added to the column shift lever. The driver information center (DIC) then shows the 6 available ranges with the current range bracketed. The bracketed range is the highest attainable range with all gears below accessible, for example, when 4th range is selected, ranges 1st through 4th are available. By using the +/- buttons on the gear select lever, the driver can select the range of gears desired for their current driving conditions.
- 1 - Manual LOW
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Manual LOW provides first gear operation only.