Code No.C1458: Free-Wheel Engage Switch System (Abnormal)




















OPERATION



DIAGNOSIS CODE SET CONDITIONS



PROBABLE CAUSES



  • Malfunction of the free-wheel engage switch
  • Damaged harness wires and connectors
  • Malfunction of the transfer-ECU

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III diagnosis code.
Check if the diagnosis code is set.

Q. Is diagnosis code No.C1457 set?
Refer to diagnosis code No.C1457: Free-wheel Engage Solenoid Valve System .
Go to Step 2.

STEP 2. M.U.T.-III data list.
Item 77: Free-wheel engage switch (Refer to data list reference table ).

Q. Is the check result normal?
Intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ).
Go to Step 3.

STEP 3. M.U.T.-III data list.
(1)Remove the free-wheel engage switch.
(2)Do not disconnect connector B-114.
(3)Turn the ignition switch to the ON position.
(4)Item 77: Free-wheel engage switch.
(5)When the free-wheel engage switch is released (OFF).
OK: M.U.T.-III display should be "OFF"
When the free-wheel engage switch is pressed (ON).
OK: M.U.T.-III display should be "ON"

Q. Is the check result normal?
Go to Step 4.
Go to Step 5.

STEP 4. Check the free-wheel engage solenoid valve.
Refer to GROUP 26 - On-vehicle Service .

Q. Is the check result normal?
Repair or replace the actuator assembly and free-wheel engage clutch (Refer to GROUP 26 - Differential Carrier and Free-wheel Clutch ).
Repair or replace the free-wheel engage solenoid valve and vacuum hoses (Refer to GROUP 26 - Solenoid Valve and Vacuum Hose ).

STEP 5. Check the free-wheel engage switch.
Refer to GROUP 26 - Differential Carrier and Free-wheel Clutch .

Q. Is the check result normal?
Go to Step 6.
Replace the free-wheel engage switch (Refer to GROUP 26 - Differential Carrier and Free-wheel Clutch ).

STEP 6. Measure the voltage at freewheel engage switch connector B-114.
(1)Disconnect the connector, and measure the voltage between terminal No.2 and earth at the wiring harness side.
(2)Turn the ignition switch to the ON position.
OK: Approx. 10.5 V

Q. Is the check result normal?
Go to Step 12.
Go to Step 7.

STEP 7. Measure the voltage at transfer-ECU connector D-123.
(1)Measure the voltage between terminal No.48 and earth at the ECU side.
(2)Transmission gear should be neutral position.
(3)Turn the ignition switch to the ON position.
OK:

  • When the transfer shift lever position is 2H, voltage should measure approx. 10.5 V.
  • When the transfer shift lever position is other than 2H, voltage should measure 1 V or less.

Q. Is the check result normal?
Go to Step 10.
Go to Step 8.

STEP 8. Connector check: B-20, D-225 intermediate connector, B-114 free-wheel engage switch connector, D-123 transfer-ECU connector.
Check for the contact with terminals.

Q. Is the check result normal?
Go to Step 9.
Repair the defective connector.

STEP 9. Check the harness between transfer-ECU connector D-123 terminal No.48 and free-wheel engage switch connector B-114 terminal No.2.
Check the output line for short circuit.

Q. Is the check result normal?
Go to Step 15.
Repair the wiring harness.

STEP 10. Connector check: B-20, D-225 intermediate connector, B-114 free-wheel engage switch connector, D-123 transfer-ECU connector.
Check for the contact with terminals.

Q. Is the check result normal?
Go to Step 11.
Repair the defective connector.

STEP 11. Check the harness between transfer-ECU connector D-123 terminal No.48 and free-wheel engage switch connector B-114 terminal No.2.
Check the output line for open circuit.

Q. Is the check result normal?
Go to Step 15.
Repair the wiring harness.

STEP 12. Measure the resistance at free-wheel engage switch connector B-114.
Disconnect the connector, and measure the resistance between terminal No.1 and earth at the wiring harness side.
OK: Continuity (2 Ω or less)

Q. Is the check result normal?
Go to Step 15.
Go to Step 13.

STEP 13. Connector check: B-20 intermediate connector, B-114 free-wheel engage switch connector.

Q. Is the check result normal?
Go to Step 14.
Repair the defective connector.

STEP 14. Check the harness between free-wheel engage switch connector B-114 terminal No.1 and earth.
Check the earth line for open circuit.

Q. Is the check result normal?
Go to Step 15.
Repair the wiring harness.

STEP 15. M.U.T.-III data list.
Item 77: Free-wheel engage switch (Refer to data list reference table ).

Q. Is the check result normal?
Intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ).
Replace the transfer-ECU.