Shift Select System Diagnosis

Circuit Description
The shift select system allows the driver to select one of two shift patterns, NORMAL or PERFORMANCE. Pressing the shift select switch button on the shifter handle changes the shift pattern. When the driver selects the PERFORMANCE shift pattern, the performance shift switch closes, which provides a ground signal to the Body Control Module (BCM) . When the BCM receives this input, it sends a message to the PCM and the Instrument Panel Control (IPC) module. This signal activates the performance shift control program in the PCM and commands the IPC module to illuminate the SHIFT indicator on the instrument panel.
The PERFORMANCE shift pattern has the following characteristics:
^ Upshifts occur at a higher vehicle speed.
^ Downshifts occur at a lower percentage throttle position
^ Engine torque output is increased in 2nd and 3rd gear.

Diagnostic Aids
^ Inspect the connectors at the controller, the component and all other circuit connecting points for an intermittent condition. Refer to Testing for Intermittent and Poor Connections in Diagrams/Diagnostic Aids.
^ Inspect the circuit wiring for an intermittent condition. Refer to Testing for Electrical Intermittents in Diagrams/Diagnostic Aids.

Test Description
The numbers below refer to the step numbers on the diagnostic table.
4. This step verifies the repair by comparing the characteristics of the shift at a specific throttle angle in each shift mode.