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U0100 Lost Communication With ECM/PCM (ECU TIME OUT)

AutoHex Online Help: Hyundai SANTAFE(CM) 2011
Component Location
General Description

CAN communication is a parallel circuit to interchange information among each units. CAN communication can share much information with units more faster and more efficiently by using specified language.

CAN-High line is twisted with CAN-Low line as a purpose in preventing from a noise.

ITM-ECU performs active control by sharing signals of engine RPM, APS, shift position, torque reduction.



DTC Description

This code related to communication line between PCU, ABS, ESP and 4WD ECM( = TCCU : Transfer Case Control Unit) is set when CAN signal from PCU, ABS, ESP can't received for more than 1sec or ECU internal error occur.

If failure is detected ITM-ECU prohibits the ITM control and cuts the current to control coil.

DTC Detecting Condition

Item

Detecting Condition

Possible Cause

DTC Strategy

ECU-ITM communication line or ECU side malfunction.

CAN HIGH/LOW circuit open/short.

Faulty CAN MODULE.

Faulty ECM/PCM

Enable Conditions

IG KEY "ON" , ENGINE "ON "

Threshold Value

When the 4WD ECM doesn't get EMS1 or EMS2 message.

Diagnostic Time

1 sec.

MIL on condition

0.5 sec.

Fail Safe

Prohibiting ITM control

Dignostic Circuit Diagram
Signal Waveform & Data

Fig.1) CAN Signal : high & low