Vehicle uses 2WD(2 wheel drive) for driving at normal speed, but sometimes it uses 4WD ECM(= TCCU : Transfer Case Control Unit) accordign to driving condition. (cornering or acceleration)
EMC(=Electric Magnetic Valve Clutch) distributes proper torque to front wheel by controling amount of current inside EMC coil.That time power pressing the multi plate clutch by apply cam is changed by a rate of EMC duty. after multi plate clutch start slip the force for acceletion at front/rear wheel is controlled at a range of 100:0 ~ 50 : 50.
ITM system has 4WD-LOCK function that can make driving force to 50:50 by compulsion according to driver's intention.
This DTC code is related to the EMC and is set If control harness has an open or short to battery source.
If failure is detected 4WD ECM(= TCCU : Transfer Case Control Unit) prohibits the ITM control and vehicle is controlled with 2WD by intercepting EMC current.
Item
Detecting Condition
Possible Cause
DTC Strategy
Voltage Monitoring
Power supply malfunction.
4WD ECM(TCCU) connector looseness and poor terminal to wire connection.
Open or short to battery in the EMC circuit
Faulty 4WD ECM.
Enable Conditions
IG KEY "ON" , ENGINE "ON "
Threshold Value
When the 4WD ECM senses that there is a short to chassis ground more than 25 times in the control circuit.
Diagnostic Time
1 sec.
MIL on condition
0.5 sec.
Fail Safe
Prohibiting ITM control
Fig.1) EMC Signal : Throttle Valve Open