P0748

U241E AUTOMATIC TRANSAXLE: AUTOMATIC TRANSAXLE SYSTEM: P0748: Pressure Control Solenoid "A" Electrical (Shift Solenoid Valve SL1)

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

DESCRIPTION

Shifting from 1st to 4th is performed in combination with the ON and OFF operation of the shift solenoid valves SL1, SL2 and S4, which are 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 valves to allow the vehicle to be operated safely Fail-Safe Chart.






MONITOR DESCRIPTION

This DTC indicates an open or short in the shift solenoid valve SL1 circuit. The ECM commands gear shifts 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 the DTC. Also, 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 Fail-Safe Chart.

MONITOR STRATEGY





TYPICAL ENABLING CONDITIONS





TYPICAL MALFUNCTION THRESHOLDS





COMPONENT OPERATING RANGE





WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. INSPECT TRANSMISSION WIRE (SHIFT SOLENOID VALVE SL1)




(a) Disconnect the B20 transmission wire connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:






NG -- INSPECT SHIFT SOLENOID VALVE SL1
OK -- Continue to next step.
2. CHECK HARNESS AND CONNECTOR (TRANSMISSION WIRE - ECM)




(a) Disconnect the B33 ECM connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- REPLACE ECM
3. INSPECT SHIFT SOLENOID VALVE SL1




(a) Remove the shift solenoid valve SL1.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:





(c) Connect the battery positive (+) lead with a 21 W bulb to terminal 2 and the negative (-) lead to terminal 1 of the solenoid valve connector. Then check that the valve moves and makes an operating sound.
OK:
Valve moves and makes operating sound.
NG -- REPLACE SHIFT SOLENOID VALVE SL1
OK -- REPAIR OR REPLACE TRANSMISSION WIRE