Circuit/System Description

2009 Chevrolet Tahoe Base, 4.8 CSECTION Circuit/System Description
WARNING: This page is about a different car, the 2011 GMC Yukon, 2011 Chevrolet Tahoe, and 2011 Cadillac Escalade. However, it is still accessible from the selected car via links, so may be relevant.

The internal mode switch assembly is a sliding contact switch located within the transmission. The internal mode switch is integrated into the Manual Shift Shaft Position Switch and is not serviced separately. The nine outputs from the switch indicate which position is selected by the transmission manual shaft. Four outputs (A, B, C, P), are range selection inputs to the transmission control module (TCM). Five outputs (R1, R2, D1, D2, S) are direction selection inputs to the hybrid powertrain control module. The input voltage at the module is high when the switch is open and low when the switch is closed to ground.

The hybrid powertrain control module compares the internal mode switch requested direction to other data to verify that the indicated direction range switch calculation is correct.

RENDER: 1.0x

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