AUTOMATIC TRANSAXLE SYSTEM, Diagnostic DTC:P0778

DTC Code DTC Name
P0778 Pressure Control Solenoid "B" Electrical (Shift Solenoid Valve SL2)

DESCRIPTION

Changing from 1st to 6th is performed by the TCM turning shift solenoid valves SL1, SL2, SL3, SL4 and SL on and off. If an open or short circuit occurs in any of the shift solenoid valves, the TCM controls the remaining normal shift solenoid valves to allow the vehicle to be operated Click here.

DTC Code DTC Detection Condition Trouble Area
P0778 An open or short circuit (output signal duty is 0% or 100%) is detected by the TCM in the shift solenoid valve SL2 circuit while driving and shifting gears (SL2 output signal duty is more than 0% and less than 100% under normal conditions) (1-trip detection logic).

  • Open or short in shift solenoid valve SL2 circuit

  • Shift solenoid valve SL2

  • TCM

MONITOR DESCRIPTION

This DTC indicates an open or short in the shift solenoid valve SL2 circuit. The TCM commands gear shifts by turning the shift solenoid valves on or off. When there is an open or short circuit in any of the shift solenoid valve circuits, the TCM detects the problem, illuminates the MIL and stores the DTC. The TCM also performs the fail-safe function and turns the other normal shift solenoid valves on or off (in case of an open or short circuit, the TCM stops sending current to the circuit).

While driving and shifting gears, if the TCM detects an open or short in the shift solenoid valve SL2 circuit, the TCM determines there is a malfunction Click here.

WIRING DIAGRAM

A01IOC4E02

INSPECTION PROCEDURE

Tech Tips

The following table shows the normal operation of shift solenoid valve SL2 when the shift lever is in D:

TCM gear shift command 1st 2nd 3rd 4th 5th 6th
Shift solenoid valve SL2 OFF OFF OFF ON ON ON

PROCEDURE


  1. INSPECT TRANSMISSION WIRE (SHIFT SOLENOID VALVE SL2)


    1. A01ITDLE17
      Text in Illustration
      *a

      Component without TCM connected

      (Transmission Wire)

      Remove the TCM.

    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      9 (SL2+) - 8 (SL2-) 20°C (68°F) 5.0 to 5.6 Ω
      9 (SL2+) - Body ground Always 10 kΩ or higher
      8 (SL2-) - Body ground Always 10 kΩ or higher
      9 (SL2+) - All other terminals except 8 (SL2-) Always 10 kΩ or higher
      8 (SL2-) - All other terminals except 9 (SL2+) Always 10 kΩ or higher

    NG

    Click here

    OK

    REPLACE TCM Click here

  2. INSPECT SHIFT SOLENOID VALVE SL2


    1. A01IOMJE06
      Text in Illustration
      *a

      Component without harness connected

      (Shift Solenoid Valve SL2)

      Remove shift solenoid valve SL2.

    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      1 - 2 20°C (68°F) 5.0 to 5.6 Ω

    3. Apply 12 V battery voltage to the shift solenoid valve and check that the valve moves and makes an operating noise.

      OK
      Measurement Condition Specified Condition

      • Battery positive (+) with a 21 W bulb → Terminal 1

      • Battery negative (-) → Terminal 2

      		 Valve moves and makes an operating noise

    NG

    REPLACE SHIFT SOLENOID VALVE SL2 Click here

    OK

    REPLACE TRANSMISSION WIRE Click here