DESCRIPTION
MONITOR DESCRIPTION
WIRING DIAGRAM
INSPECTION PROCEDURE
INSPECT NO. 1 TRANSMISSION WIRE (SHIFT SOLENOID VALVE SL1)
CHECK HARNESS AND CONNECTOR (NO. 1 TRANSMISSION WIRE - ECM)
INSPECT 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 the ON and OFF operation of the shift solenoid valves SL1, SL2, S1, S2, S3, S4 and SR, which are controlled by the ECM. If an open or short circuit occurs in the shift solenoid valves, the ECM controls the remaining normal shift solenoid valves to allow the vehicle to be operated safely ().
| DTC Code | DTC Detection Condition | Trouble Area |
| P0748 | 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).
The output signal duty equals 100%.
- The SL1 output signal duty is less than 100% under normal conditions.
| Open or short in shift solenoid valve SL1 circuit
Shift solenoid valve SL1
ECM
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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 open or short circuited solenoid.
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 that there is a malfunction ().
WIRING DIAGRAM
INSPECTION PROCEDURE
- The shift solenoid valve SL1 turns ON/OFF normally when the shift lever is in D:
| ECM gear shift command | 1st | 2nd | 3rd | 4th | 5th | 6th |
| Shift solenoid valve SL1 | OFF | OFF | OFF | OFF | ON | ON |
| 1.INSPECT NO. 1 TRANSMISSION WIRE (SHIFT SOLENOID VALVE SL1) |
Disconnect the No. 1 transmission wire connector.
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 |
| 11 (SL1+) - Body ground | Always | 10 kΩ or higher |
| 3 (SL1-) - Body ground | Always | 10 kΩ or higher |
Text in Illustration| *a | Component without harness connected
(No. 1 Transmission Wire) |
| 2.CHECK HARNESS AND CONNECTOR (NO. 1 TRANSMISSION WIRE - ECM) |
Disconnect the ECM connector.
Measure the resistance according to the value(s) in the table below.
- Standard Resistance:
for LHD| Tester Connection | Condition | Specified Condition |
| C45-13 (SL1+) - C45-12 (SL1-) | 20°C (68°F) | 5.0 to 5.6 Ω |
| C45-13 (SL1+) - Body ground | Always | 10 kΩ or higher |
| C45-12 (SL1-) - Body ground | Always | 10 kΩ or higher |
for RHD| Tester Connection | Condition | Specified Condition |
| C46-13 (SL1+) - C46-12 (SL1-) | 20°C (68°F) | 5.0 to 5.6 Ω |
| C46-13 (SL1+) - Body ground | Always | 10 kΩ or higher |
| C46-12 (SL1-) - Body ground | Always | 10 kΩ or higher |
Text in Illustration| *1 | for LHD |
| *2 | for RHD |
| *a | Front view of wire harness connector
(to ECM) |
| | REPAIR OR REPLACE HARNESS OR CONNECTOR |
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| 3.INSPECT SHIFT SOLENOID VALVE SL1 |
Remove the shift solenoid valve SL1.
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 |
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 |
Text in Illustration| *a | Component without harness connected
(Shift Solenoid Valve SL1) |
| | REPLACE SHIFT SOLENOID VALVE SL1 ()
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| OK | |
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| REPAIR OR REPLACE NO. 1 TRANSMISSION WIRE ()
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