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For 1990-2009 cars only

DTC P0763 - Shift Solenoid 3 Control Circuit High Voltage


Object Number: 870978  Size: MF

Circuit Description

Shift solenoid 3 is used to supply and relieve fluid pressure to the 3rd gear clutch pack. Shift solenoid 3 is turned electrically ON/hydraulically OFF, relieving pressure to 3rd gear clutch, during 1st , 2nd and 4th gear operation. The powertrain control module (PCM) controls shift solenoid 3 by controlling an internal driver that pulls the solenoid circuit to ground. During normal 3rd gear shift operation, the PCM will turn OFF , open the driver, shift solenoid 3 and keep it OFF until 4th gear is commanded ON or until a downshift occurs. The PCM will PWM the pressure control solenoid to adapt shift timing. The shift solenoid 3 circuit is monitored for low and high voltage faults. DTC P0763 sets when shift solenoid 3 is commanded ON and the feedback voltage at the PCM is high.

DTC Parameters

DTC P0763 will set if shift solenoid 3 feedback voltage is greater than 1.25 volts with shift solenoid 3 commanded ON 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  P0763 diagnostic runs continuously with fuel pump relay and shift solenoid 3 commanded ON.

DTC P0763 is a type D DTC.

*Applicable to vehicles built after June 2000.

Diagnostic Aids

To locate an intermittent problem, start engine with transaxle in Park and monitor the SHIFT SOL. 3 - HIGH VOLT test. When a fault, short to voltage or shorted solenoid, exists, the scan tool will display TEST FAIL.

The test will fail only when the device is being commanded ON and the voltage at the PCM is high. The test updates every 100 milliseconds whenever the ignition is turned ON and the device is being commanded ON via the scan tool or PCM.

If a short across the solenoid or a short to voltage on circuit 1223 exists, the PCM will open the driver circuit for protection and the feedback voltage will be high.

Shift solenoid 3 resistance: 3.8-7.2 ohms

Nominal value: 4.5 ohms at 68°F


Object Number: 875492  Size: FP