Dtc P0748 Pressure Control Solenoid A Electrical (Shift Solenoid Valve Sl1)
Drivetrain. Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25
DESCRIPTION
MONITOR DESCRIPTION
WIRING DIAGRAM
INSPECTION PROCEDURE
INSPECT TRANSMISSION WIRE (SHIFT SOLENOID VALVE SL1)
CHECK HARNESS AND CONNECTOR (TRANSMISSION WIRE - TCM)
INSPECT SHIFT SOLENOID VALVE SL1
DTC P0748 Pressure Control Solenoid "A" Electrical (Shift Solenoid Valve SL1) |
DESCRIPTION
Shifting from 1st to 5th is performed in combination with the ON and OFF operation of shift solenoid valves SL1, SL2, S1, S2 and SR, which are controlled by the TCM. If an open or short circuit occurs in one of the shift solenoid valves, the TCM controls the remaining normal shift solenoid valves to allow the vehicle to be operated smoothly (HILUX_TGN26 RM000000O8L0MCX.html).DTC Code
| DTC Detection Condition
| Trouble Area
|
P0748
| The TCM 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 100%.
- HINT:
- SL1 output signal duty is less than 100% under normal conditions.
| - Open or short in shift solenoid valve SL1 circuit
- Shift solenoid valve SL1
- TCM
|
MONITOR DESCRIPTION
This DTC indicates an open or short in the shift solenoid valve SL1 circuit. The TCM 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 TCM detects the problem, illuminates the MIL and stores the DTC. Then the TCM performs the fail-safe function and turns the other normal shift solenoid valves ON/OFF. In the 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 (HILUX_TGN26 RM000000O8L0MCX.html).
WIRING DIAGRAM
INSPECTION PROCEDURE
- HINT:
- Shift solenoid valve SL1 is turned ON/OFF normally when the shift lever is in D.
TCM gear shift command
| 1st
| 2nd
| 3rd
| 4th
| 5th
|
Shift solenoid valve SL1
| OFF
| OFF
| OFF
| OFF
| ON
|
| 1.INSPECT TRANSMISSION WIRE (SHIFT SOLENOID VALVE SL1) |
Disconnect the transmission wire connector.
Measure the resistance according to the value(s) in the table below.
- Standard Resistance:
Tester Connection
| Condition
| Specified Condition
|
12 (SL1+) - 4 (SL1-)
| 20°C (68°F)
| 5.0 to 5.6 Ω
|
12 (SL1+) - Body ground
| 20°C (68°F)
| 10 kΩ or higher
|
4 (SL1-) - Body ground
| 20°C (68°F)
| 10 kΩ or higher
|
Text in Illustration*a
| Component without harness connected
(Transmission Wire)
|
| 2.CHECK HARNESS AND CONNECTOR (TRANSMISSION WIRE - TCM) |
Disconnect the TCM connector.
Measure the resistance according to the value(s) in the table below.
- Standard Resistance:
Tester Connection
| Condition
| Specified Condition
|
C24-9 (SL1+) - C24-8 (SL1-)
| 20°C (68°F)
| 5.0 to 5.6 Ω
|
C24-9 (SL1+) - Body ground
| 20°C (68°F)
| 10 kΩ or higher
|
C24-8 (SL1-) - Body ground
| 20°C (68°F)
| 10 kΩ or higher
|
Text in Illustration*a
| Rear view of wire harness connector
(to TCM)
|
| | REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|
| 3.INSPECT SHIFT SOLENOID VALVE SL1 |
Remove 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)
|
