Code No. C1437: F/W actuator terminal high VOLT.
Code No. C1438: F/W actuator terminal low VOLT.
Code No. C1439: F/W actuator terminal HI current


OPERATION


The freewheel engage switch is turned ON when the freewheel solenoid is activated and the condition is shifted to the 4WD condition. The power supply voltage is imposed to the freewheel engage switch from the transfer-ECU, and when the freewheel engage switch is turned ON, the power supply voltage from the transfer-ECU is earthed.

DIAGNOSIS CODE SET CONDITIONS



PROBABLE CAUSES



DIAGNOSIS PROCEDURE

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

Q. Is the diagnosis code set?
Troubleshoot the transfer-ECU. Refer to .
Go to Step 2.

STEP 2. Check the freewheel solenoid.
Refer to GROUP 26 - Free wheel solenoid valve operation check .

Q. Is the check result normal?
Go to Step 3.
Replace the freewheel solenoid (Refer to GROUP 26 - Differential carrier and free wheeling clutch ).

STEP 3. Check of short to power supply, short to earth, and open circuit in FSL+, FSL- line between transfer-ECU and freewheel solenoid connector.

Q. Is the check result normal?
Go to Step 4.
Repair the connector(s) or wiring harness.

STEP 4. Retest the system
Check that the freewheel solenoid functions work normally.

Q. Is the check result normal?
The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to use Troubleshooting/inspection Service Points - How to Cope with Intermittent Malfunction ).
Replace the transfer-ECU (Refer to ).