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For 1990-2009 cars only

DTC P0756 - Shift Solenoid 2 Control Circuit Low Voltage


Object Number: 870984  Size: MF

Circuit Description

Shift solenoid 2 is used to supply and relieve fluid pressure to the 2nd gear clutch pack. Shift solenoid 2 is turned electrically ON/hydraulically OFF, relieving pressure to 2nd gear clutch, during 1st , 3rd and 4th gear operation. The powertrain control module (PCM) controls shift solenoid 2 by controlling an internal driver that pulls the solenoid circuit to ground. During normal 2nd gear shift operation, the PCM will turn OFF, open the driver, shift solenoid 2 and keep it OFF until 3rd gear is commanded ON or until a downshift occurs. The PCM will PWM the pressure control solenoid to adapt shift timing. The shift solenoid 2 circuit is monitored for low and high voltage faults. DTC P0756 sets when shift solenoid 2 is commanded OFF and the feedback voltage at the PCM is low.

DTC Parameters

DTC P0756 will set if shift solenoid 2 feedback voltage is less than 1.25 volts with shift solenoid 2 commanded OFF when:

    • The condition exists for longer than 100 milliseconds (2001)*.
    • The condition exists for longer than 100 milliseconds, solenoid is turned OFF for 1 minute, then condition exists again for longer than 100 milliseconds (2000).
    • The fuel pump relay is commanded ON.

DTC P0756 diagnostic runs continuously with fuel pump relay commanded ON and shift solenoid 2 commanded OFF.

DTC P0756 is a type D DTC.

*Applicable to vehicles built after June 2000.

Diagnostic Aids

To locate an intermittent problem, use scan tool to command TRANS. SOLENOID POWER ON, while monitoring the SHIFT SOL. 2 - LOW VOLT or SHIFT SOL. 2 - OPEN test. When a fault, open or short to ground exists, the Scan tool will display TEST FAIL for both tests.

The tests will fail only when the device is being commanded OFF and the voltage at the PCM is low. The tests update every 100 milliseconds whenever the ignition is turned ON and the device is being commanded OFF via the scan tool or PCM.

Shift solenoid 2 resistance: 3.8-7.2 ohms.

Nominal value: 4.5 ohms at 68°F


Object Number: 875490  Size: FP