P0748

U660E 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 6th is performed in combination with "ON" and "OFF" operation of the shift solenoid valves SL1, SL2, SL3, SL4 and SL which is controlled by the TCM. 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 smoothly Fail-Safe Chart.

MONITOR DESCRIPTION

This DTC indicates an open or short in the shift solenoid valve SL1 circuit. The TCM causes gear shifts to occur by turning the shift solenoid valves on or off. When there is an open or short circuit in any shift solenoid valve circuit, the TCM detects the problem and 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 between 4th and 5th gears, if the TCM detects an open or short in the shift solenoid valve SL1 circuit, the TCM determines there is a malfunction Fail-Safe Chart.

MONITOR STRATEGY

TYPICAL ENABLING CONDITIONS

ALL:

Condition (A):

Condition (B):

Condition (C):

TYPICAL MALFUNCTION THRESHOLDS

When one of the following conditions is met: Condition (A), (B) or (C)

Condition (A) and (B)

Condition (C)

COMPONENT OPERATING RANGE

WIRING DIAGRAM

INSPECTION PROCEDURE
HINT: The shift solenoid valve SL1 is turned on or off automatically when the shift lever is in the D position:

PROCEDURE

1. INSPECT TRANSMISSION WIRE (SL1)

(a) Remove the TCM from the transaxle.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:

OK -- REPLACE TCM
NG -- Continue to next step.
2. 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 a positive (+) lead through a 21 W bulb to terminal 2 and a negative (-) lead to terminal 1 of the solenoid valve connector, then check the movement of the valve.
OK:
The solenoid makes an operating sound.
NG -- REPLACE SHIFT SOLENOID VALVE SL1
OK -- REPLACE TRANSMISSION WIRE