AUTOMATIC TRANSMISSION SYSTEM, Diagnostic DTC:P0748

DTC Code DTC Name
P0748 Pressure Control Solenoid "A" Electrical (Shift Solenoid Valve SL1)

DESCRIPTION

Shifting from 1st to 6th gear is performed in combination with "ON" and "OFF" operation of the shift solenoid valves SL1, SL2, S1, S2, S3, S4 and SR which is controlled by the ECM. If an open or short circuit occurs in any of the shift solenoid valves, the ECM controls the remaining normal shift solenoid valve to allow the gears to be shifted smoothly.

DTC No. Detection Item DTC Detection Condition Trouble Area MIL Memory
P0748 Pressure Control Solenoid "A" Electrical (Shift Solenoid Valve SL1)

The ECM checks for an open or short in the shift solenoid valve SL1 circuit while driving and shifting between 4th and 5th gear. (1-trip detection logic)


  • Output signal duty equals to 100%.

    (NOTE: SL1 output signal duty is less than 100% under normal condition.)

  • Open or short in shift solenoid valve SL1 circuit

  • Shift solenoid valve SL1

  • ECM

 Comes on DTC stored

MONITOR DESCRIPTION

This DTC indicates an open or short in the shift solenoid valve SL1 circuit. The ECM commands gearshift by turning the shift solenoid valves "ON/OFF". When there is an open or short circuit in any shift solenoid valve circuit, the ECM detects the problem, illuminates the MIL and stores this DTC. The ECM performs the fail-safe function and turns the other normal shift solenoid valves "ON/OFF". (In case of an open or short circuit, the ECM stops sending current to the circuit.)

While driving and shifting between 4th and 5th gear, if the ECM detects an open or short in the shift solenoid valve SL1 circuit, the ECM determines there is a malfunction.

WIRING DIAGRAM

A01MV6EE10
*a Shift Solenoid Valve SL1
*b Transmission Wire

CAUTION / NOTICE / HINT

Note

Perform registration and/or initialization when parts related to the automatic transmission are replaced.

Click here

Tech Tips


  • The shift solenoid valve SL1 is turned on/off normally when the shift lever is in the D position:

    ECM commanded gear 1st 2nd 3rd 4th 5th 6th
    Shift solenoid valve SL1 OFF OFF OFF OFF ON ON

PROCEDURE


  1. INSPECT TRANSMISSION WIRE (SHIFT SOLENOID VALVE SL1)


    1. A01MVFBC76
      *a

      Component without harness connected

      (Transmission Wire)

      Disconnect the transmission wire connector from the transmission.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      11 (SL1+) - 3 (SL1-) 20°C (68°F) 5.0 to 5.6 Ω

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

      Standard Resistance (Check for short)
      Tester Connection Condition Specified Condition
      11 (SL1+) - Body ground Always 10 kΩ or higher
      3 (SL1-) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    INSPECT SHIFT SOLENOID VALVE SL1 Click here

    OK

  2. CHECK HARNESS AND CONNECTOR (TRANSMISSION WIRE - ECM)


    1. A01MVU8C08
      *a

      Rear view of wire harness connector

      (to ECM)

      Connect the transmission connector to the transmission.

    2. Disconnect the F1 connector from the ECM.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      F1-3 (SL1+) - F1-2 (SL1-) 20°C (68°F) 5.0 to 5.6 Ω

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

      Standard Resistance (Check for short)
      Tester Connection Condition Specified Condition
      F1-3 (SL1+) - Body ground Always 10 kΩ or higher
      F1-2 (SL1-) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE ECM Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  3. INSPECT SHIFT SOLENOID VALVE SL1


    1. B003VU8C44
      *a Shift Solenoid Valve SL1

      Remove the shift solenoid valve SL1.

    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. Connect the a battery positive (+) lead with a 21 W bulb to terminal 1 and a battery negative (-) lead to terminal 2 of the solenoid valve connector, then check the movement of the valve.

      OK
      The solenoid makes an operating sound.
      Result
      Proceed to
      OK
      NG

    OK

    REPAIR OR REPLACE TRANSMISSION WIRE Click here

    NG

    REPLACE SHIFT SOLENOID VALVE SL1 Click here