P0748

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

DESCRIPTION
Shifting from 1st to 6th 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 one of the shift solenoid valves, the ECM controls the remaining normal shift solenoid valve to allow the vehicle to be operated smoothly.

P0748:

Reference (Using an oscilloscope):
Check the waveform between the terminals SL1+ and SL1- of the ECM connector





Standard: Refer to the illustration.





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 and illuminates the MIL and stores the DTC. And 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 gears, if the ECM detects an open or short in the shift solenoid valve SL1 circuit, the ECM determines there is a malfunction.

MONITOR STRATEGY





TYPICAL ENABLING CONDITIONS





TYPICAL MALFUNCTION THRESHOLDS

WIRING DIAGRAM:

INSPECTION PROCEDURE

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

Steps 1-2:

Step 3: