Code No. P0740: Malfunction of Lockup Solenoid Valve




DIAGNOSTIC FUNCTION


CVT-ECU determines malfunction by detecting the abnormality in the lockup solenoid valve.

JUDGEMENT CRITERIA


Specified amount of current is not flown to the lockup solenoid valve because of the open or short circuit.

PROBABLE CAUSES




DIAGNOSTIC PROCEDURE


STEP 1. M.U.T.-III data list



  • Item 31: Lockup solenoid output current
  • Item 30: Lockup solenoid monitoring current
OK: Check if the output current and monitoring current differ largely.

Q. Is the check result normal?

Intermittent malfunction
Go to Step 2.

STEP 2. Check for open circuit and short to earth in LULS line between the CVT-ECU connector and the CVT assembly connector


Q. Is the check result normal?

Go to Step 3.
Repair the connector(s) or wiring harness.

STEP 3. Lockup solenoid valve single unit check


Refer to .

Q. Is the check result normal?

Go to Step 4.
Replace the valve body assembly.

STEP 4. Symptom recheck after erasing diagnosis code


Q. Is the check result normal?

Intermittent malfunction
Replace CVT-ECU.