Code No.P2774: 4LLc detection switch system (Open circuit)


4LLC OPERATION DETECTION SWITCH SYSTEM CIRCUIT



OPERATION



COMMENTS ON TROUBLE SYMPTOM



PROBABLE CAUSES
  • Malfunction of the 4LLc detection switch
  • Damaged harness wires and connectors
  • Malfunction of the A/T-ECU

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III other system diagnosis codes
Check whether the transfer system diagnosis codes are set or not.

Q. Is the diagnosis code set?
YES : Diagnose the transfer system (Refer to GROUP 22A - Troubleshooting ).
Go to Step 2.

STEP 2. M.U.T.-III data list
Item 31: 4LLc detection switch (Refer to data list reference table ).

Q. Is the check result normal?
Go to Step 6.
Go to Step 3.

STEP 3. Connector check: C-09 4LLc detection switch connector
Check for the contact with terminals.

Q. Is the check result normal?
Go to Step 4.
Repair the defective connector.

STEP 4. Check the 4LLc detection switch.
Refer to .

Q. Is the check result normal?
Go to Step 5.
Replace the 4LLc detection switch.

STEP 5. Measure the voltage at 4LLc detection switch connector C-09.
(1)Disconnect the connector, and measure the voltage between terminal No.1 and earth at the wiring harness side.
(2)Turn the ignition switch to the ON position.
OK: System voltage

Q. Is the check result normal?
Go to Step 6.
Go to Step 7.

STEP 6. Check whether the diagnosis code is reset.
Check again if the diagnosis code is set.

Q. Is diagnosis code No.P2774 set?
Replace the A/T-ECU.
Intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ).

STEP 7. Connector check: D-225 intermediate connector, D-139 A/T-ECU connector
Check for the contact with terminals.

Q. Is the check result normal?
Go to Step 8.
Repair the defective connector.

STEP 8. Check the harness between 4LLc detection switch connector C-09 terminal No.1 and A/T-ECU connector D-139 terminal No.33.
Check the power supply line for open circuit.

Q. Is the check result normal?
Go to Step 6.
Repair the wiring harness.