P0758

Diagnostic Chart:

Wiring Diagram:

Circuit Description

The 2-3 Shift Solenoid Valve (2-3 SS Valve) controls the fluid acting on the 2-3 shift valves. The solenoid is a normally-open exhaust valve. In combination with the 1-2 Shift Solenoid Valve, the 2-3 SS Valve allows four different shifting combinations. The solenoid is attached to the control valve body within the transmission. Circuit 439 supplies ignition voltage directly to the 2-3 SS Valve. The PCM controls the solenoid by providing the ground path through circuit 1223.

If the PCM detects a continuous open or short to ground in the 2-3 SS Valve circuit or in the 2-3 SS Valve, then DTC P0758 sets. DTC P0758 is a type A DTC.

Conditions for Setting the DTC
- The engine speed is greater than 400 RPM and not in fuel cut off.
- The system voltage is 10-16 volts.
- The PCM commands the solenoid ON and the voltage remains high (Battery Positive Voltage).
- The PCM commands the solenoid OFF and the voltage remains low (0 volts).
- All conditions are met for 5 seconds.

Action Taken When the DTC Sets
- The PCM commands a soft landing to third gear.
- The PCM commands maximum line pressure.
- The PCM inhibits 4th gear if in hot mode.
- The PCM freezes shift adapts from being updated.
- The PCM inhibits TCC engagement
- The PCM illuminates the Malfunction Indicator Lamp (MIL).

Conditions for Clearing the MIL/DTC
- The PCM turns OFF the MIL after three consecutive ignition cycles without a failure reported.
- A scan Tool can clear the DTC from the PCM history. The PCM clears the DTC from the PCM history if the vehicle completes 40 warm-up cycles without a failure reported.
- The PCM cancels the DTC default actions when the fault no longer exists and the ignition is OFF long enough in order to power down the PCM.

Diagnostic Aids

Inspect the wiring for any poor electrical connections at the PCM. Inspect the wiring at the TCC brake switch. Look for the following problems:
- A bent terminal
- A backed out terminal
- A damaged terminal
- Poor terminal tension
- A chafed wire
- A broken wire inside the insulation
- When diagnosing for an intermittent short or an open, massage the wiring harness while watching the test equipment for changes.
- Refer to Shift Solenoid Valve State and Gear Ratio

Test Description

The numbers below refer to the step numbers on the diagnostic chart.
4. This step verities that the 2-3 SS Valve and the Automatic Transmission wiring harness are functioning normally.
6. This step verifies that the ignition supplies power to the 2-3 SS Valve through the PCM IGN fuse.
16. This step verifies that the valve's resistance is within specifications.