Code No. P0741:
Abnormality in Lock-up Function
DIAGNOSTIC FUNCTION
Abnormality is detected by the CVT-ECU when the torque converter slip speed is high during
lock-up control.
JUDGEMENT CRITERIA
While the lock-up control, all the conditions listed below remain for 30 seconds.
- Slip speed is higher than the judgement value.
- The lock-up differential pressure is more than 0.2 MPa.
PROBABLE CAUSES
- Malfunction of valve body assembly (Faulty lock-up solenoid valve)
- Malfunction of the CVT assembly
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STEP 1. M.U.T.-III diagnosis code
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Q.
Are diagnosis codes P2763 or P2764 set?
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Carry out the appropriate troubleshooting.
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Go to Step 2
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STEP 2. Measure the output wave pattern of the lock-up solenoid valve
at CVT-ECU connector (LULS terminal).
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(1)Connect the CVT assembly connector.
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(2)Selector lever position: D
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(3)Accelerator pedal opening angle: 12.5% or less
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(4)Drive at a constant speed of approx. 20 km/h
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(5)Connect an oscilloscope, and measure the voltage between CVT-ECU connector LULS
terminal and body earth. OK: A wave pattern such as the one shown on (Check
Procedure Using an Oscilloscope) should be output. There should be no noise in the output wave
pattern.
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Q.
Is the check result normal?
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Go to Step 3
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Refer to diagnosis code No.P2763: Malfunction of Lock-up Solenoid Valve (open) ,
or diagnosis code No.P2764: Malfunction of Lock-up Solenoid Valve (short) .
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STEP 3. Symptom recheck after erasing diagnosis code
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Turn the ignition switch to the "LOCK" (OFF) position, and wait for one minute. Then,
drive the vehicle for a while and check again.
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Q.
Is the diagnosis code set?
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Replace the CVT assembly.
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Intermittent malfunction.
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