Lexus IS250 IS220d GSE20 ALE20 - A960E AUTOMATIC TRANSMISSION
INSPECT TRANSMISSION WIRE (S3)
CHECK HARNESS AND CONNECTOR (TRANSMISSION WIRE - ECM)
INSPECT SHIFT SOLENOID VALVE S3
DTC P0979 Shift Solenoid "C" Control Circuit Low (Shift Solenoid Valve S3)
DTC P0980 Shift Solenoid "C" Control Circuit High (Shift Solenoid Valve S3)
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 either of the shift solenoid valves, the ECM controls the remaining normal shift solenoid valve to allow the vehicle to be operated smoothly. (In case of an open or short circuit, the ECM stops sending current to the circuit.) Fail safe function .
| DTC No. | DTC Detection Condition | Trouble Area |
| P0979 | ECM detects short in solenoid valve S3 circuit 2 times when solenoid valve S3 is operated (1-trip detection logic) | Short in shift solenoid valve S3 circuit Shift solenoid valve S3 ECM |
| P0980 | ECM detects open in solenoid valve S3 circuit 2 times when solenoid valve S3 is operated (1-trip detection logic) | Open in shift solenoid valve S3 circuit Shift solenoid valve S3 ECM |
MONITOR DESCRIPTION
These DTCs indicate an open or short in the shift solenoid valve S3 circuit. 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. When the shift solenoid valve S3 is on, if resistance is 8 Ω or less, the ECM determines there is a short in the shift solenoid valve S3 circuit.
When the shift solenoid valve S3 is off, if resistance is 100 kΩ or more, the ECM determines there is an open in the shift solenoid valve S3 circuit .
WIRING DIAGRAM
INSPECTION PROCEDURE
- HINT:
| ECM command gearshift | 1st | 2nd | 3rd | 4th | 5th | 6th |
| Shift solenoid valve S3 | ON | ON | ON | OFF | OFF | OFF |
| 1.INSPECT TRANSMISSION WIRE (S3) |
Disconnect the transmission wire connector from the transmission.
Measure the resistance according to the value(s) in the table below.
- Standard resistance:
Tester Connection Specified Condition
20°C (68°F)7 - Body ground 11 to 15 Ω
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| OK | |
| 2.CHECK HARNESS AND CONNECTOR (TRANSMISSION WIRE - ECM) |
Connect the transmission connector to the transmission.
Disconnect the connector from the ECM.
Measure the resistance according to the value(s) in the table below.
- Standard resistance:
Tester Connection Specified Condition
20°C (68°F)E4-17 (S3) - Body ground 11 to 15 Ω
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| OK | ||
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| 3.INSPECT SHIFT SOLENOID VALVE S3 |
Remove the shift solenoid valve S3.
Measure the resistance according to the value(s) in the table below.
- Standard resistance:
Tester Connection Specified Condition
20°C (68°F)Solenoid Connector (S3) - Solenoid Body (S3) 11 to 15 Ω
Connect the positive (+) lead to the terminal of the solenoid connector, and the negative (-) lead to the solenoid body.
- OK:
- The solenoid makes an operating sound.
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| OK | ||
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