- ECM detects open or short in shift solenoid valve SL1 circuit while driving and shifting between 4th and 5th gear. (1-trip detection logic)
- Output signal duty is 100%.
| Last Modified: 11-29-2007 | 1.6 C | |
| Service Category: Drivetrain | Section: Automatic Transmission/Transaxle | |
| Model Year: 2008 | Model: Sequoia | Doc ID: RM000000W8F04MX |
| Title: A750F AUTOMATIC TRANSMISSION / TRANSAXLE: AUTOMATIC TRANSMISSION SYSTEM: DESCRIPTION (2008 Sequoia) | ||
|
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 the shift solenoid valves SL1, SL2, S1, S2 and SR which are 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 valves to allow the vehicle to be operated smoothly
.
|
DTC No. |
DTC Detection Condition |
Trouble Area |
|---|---|---|
|
P0748 |
HINT: SL1 output signal duty is less than 100% under normal condition. |
|
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. 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
|
Related DTCs |
P0748: Shift solenoid valve SL1/Range check |
|
Required sensors/Components |
Shift solenoid valve SL1 |
|
Frequency of operation |
Continuous |
|
Duration |
1 second |
|
MIL operation |
Immediately |
|
Sequence of operation |
None |
TYPICAL ENABLING CONDITIONS
All
|
The monitor will run whenever the following DTCs are not present |
None |
All of the following conditions are met: Condition (A) and (B)
Condition (A)
|
Battery voltage |
12 V or more |
|
Ignition switch |
ON |
|
Starter |
OFF |
Condition (B)
|
Battery voltage |
10 V or more and less than 12 V |
|
CPU commanded duty |
Less than 75% |
|
Ignition switch |
ON |
|
Starter |
OFF |
TYPICAL MALFUNCTION THRESHOLDS
|
Output signal duty |
100% |
COMPONENT OPERATING RANGE
|
Output signal duty |
More than 3% and less than 100% |
WIRING DIAGRAM
INSPECTION PROCEDURE
HINT:
The shift solenoid valve SL1 is turned on/off normally when the shift lever is in D.
|
ECM gear shift command |
1st |
2nd |
3rd |
4th |
5th |
|
Shift solenoid valve SL1 |
OFF |
OFF |
OFF |
OFF |
ON |
PROCEDURE
|
1. |
INSPECT TRANSMISSION WIRE (SHIFT SOLENOID VALVE SL1) |
|
(a) Disconnect the D41 transmission wire connector. |
(b) 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 |
Always |
10 kΩ or higher |
|
4 (SL1-) - Body ground |
Always |
10 kΩ or higher |
|
|
2. |
CHECK HARNESS AND CONNECTOR (TRANSMISSION WIRE - ECM) |
|
(a) Disconnect the D56 ECM connector. |
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
D56-14 (SL1+) - D56-15 (SL1-) |
20°C (68°F) |
5.0 to 5.6 Ω |
|
D56-14 (SL1+) - Body ground |
Always |
10 kΩ or higher |
|
D56-15 (SL1-) - Body ground |
Always |
10 kΩ or higher |
|
|
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:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
1 - 2 |
20°C (68°F) |
5.0 to 5.6 Ω |
(c) Connect the battery positive (+) lead with a 21 W bulb to terminal 1 and the negative (-) lead to terminal 2 of the solenoid valve connector. Then check that the valve moves and makes an operating noise.
OK:
Valve moves and makes an operating noise.
|
|
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