P0758

DTC P0758












Circuit Description with 4L30-E Automatic Transmission
The 2-3 shift solenoid valve is located in the valve body of the transmission main case. The TCM selects the required gear by turning the appropriate solenoid ON or OFF, enabling the transmission to shift. Refer to Shift Solenoid Valve State and Gear Ratio.
The Transmission Control Module (TCM) provides voltage to the solenoid through an internal power control relay. The TCM uses a second driver to control the solenoid ground. The controlled ground driver reports feedback voltage to the TCM. When the TCM commands the 2-3 shift solenoid valve ON, the voltage of the control circuit should be approximately 0 volts. When the TCM commands the 2-3 shift solenoid valve OFF, the voltage of the control circuit should be approximately system voltage.
When the TCM detects a continuous open, short to power or short to ground in the 2-3 Shift Solenoid valve circuit, then DTC P0758 sets. DTC P0758 is a type B DTC.

Conditions for Running the DTC
The ignition is ON. The TCM power control relay is closed.

Conditions for Setting the DTC
DTC P0758 sets of any one of the following conditions occur in 0.18 seconds:
^ The 2-3 Shift Solenoid valve is commanded off and the feedback voltage is lower than 2.45 volts.
^ The 2-3 Shift Solenoid valve is commanded off and the feedback voltage is between 2.45 to 3.53 volts.
^ The 2-3 Shift Solenoid valve is commanded on and the feedback voltage is greater than 4.02 volts.

Action Taken When the DTC Sets
^ The TCM flashes the sport mode lamp and sends a MIL request to the ECM on the second consecutive drive trip that the diagnostic runs and fails. The ECM then illuminates the MIL.
^ The ECM records the operating conditions in the Freeze Frame at the time of the MIL request from the TCM.
^ The transmission operates in the default mode (maximum line pressure, command 4th gear inhibit TCC, freeze shift adapts).

Conditions for Clearing the MIL/DTC
^ The ECM turns off the MIL after three consecutive drive trips during which the TCM sends no MIL request.
^ A History DTC clears after forty consecutive warm-up cycles, if no failures are present by this diagnostic or any other emission related diagnostic.
^ The scan tool clears the MIL/DTC.
^ The TCM cancels the DTC default mode actions when the ignition switch is Off long enough in order to power down the TCM.

Test Description
The numbers below refer to the step numbers on the diagnostic table.
2. Listen for an audible click when the solenoid energizes.