P1728

DTC P1728 EMC-open/short to battery

Component Location:

Description:

General Description
Vehicle uses 2WD (2 wheel drive) for driving at normal speed, but sometimes it uses 4WD (4 wheel drive) according to driving condition (cornering or acceleration). EMC (Electric Magnetic 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 acceleration 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.

DTC Description
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 TCCU prohibits the ITM control and vehicle is controlled with 2WD by intercepting EMC current.

DTC Detecting Condition:

Schematic Diagram:

Signal Waveform:

Terminal and Connector Inspection
1. Many malfunctions in the electrical system are caused by poor harness and terminals. Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.
2. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration or damage.
3. Has a problem been found?

YES
1) Repair as necessary and go to "Verification of Vehicle Repair" procedure below.

NO
1) Go to " CAN Signal Inspection " procedure.

EMC Signal Inspection
1. Ignition ON, Engine: ON.
2. TCCU connector: Connect.





3. Monitor signal waveform between terminal 4, 5 of TCCU harness connector and chassis ground.
4. Shift to N Range.
A. Specification: Signal Waveform & Data

CAUTION: The above value is only for reference. The actual value may differ from it according to various engine conditions.

5. Is EMC Signal display near the specified value?

YES
1) Fault is intermittent caused by poor contact in the sensor's and/or TCCU's connector or was repaired and TCCU memory was not cleared.Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and then go to "Verification of Vehicle Repair" procedure below.

NO
1) Go to " EMC Wiring Battery Short Inspection " procedure.

EMC Wiring Battery Short Inspection
1. IG "OFF" & ENG "OFF"
2. Electric Magnet Valve Clutch,TCCU connector: Disconnect.
3. IG "ON".





4. Measure voltage between terminal 1 of EMC harness connector and chassis ground.
A. Specification: 0 V

CAUTION: The above value is only for reference. The actual value may differ from it according to various engine conditions.

5. Is voltage display near the specified value?

YES
1)Go to " EMC Harness Open Inspection " procedure.

NO
1) Check for short to battery in EMC harness.
2) Repair as necessary and then go to "Verification of Vehicle Repair" procedure below.

EMC Harness Open Inspection
1. IG "OFF" & ENG "OFF".
2. Electric Magnet Valve Clutch, TCCU connector: Disconnect.





3. Measure resistance between terminal 1 or 2 of Electric Magnet Valve Clutch harness connector and terminal 26 or 13 of TCCU harness connector.
A. Specification: 1 ohm below.

CAUTION: The above value is only for reference. The actual value may differ from it according to various engine conditions.

4. Is resistance display near the specified value?

YES
1) Go to " Component inspection " procedure.

NO
1) Check for open in EMC harness.
2) Repair as necessary and then go to "Verification of Vehicle Repair" procedure below.

Component Inspection
1. IG "OFF" & ENG "OFF"
2. EMC connector : Disconnect.





3. Measure the resistance(Component side) between terminals "1" and "2" of the "Electric Magnet Valve Clutch.
A. Specification: Approx. 1.8 ~ 2.2 ohms

CAUTION: The above value is just for reference. The actual value may differ from it according to various engine conditions.

4. Is resistance display near the specified value?

YES
1) Substitute with a known-good "TCCU" and check for proper operation. If the problem is corrected, replace "TCCU" and then go to "Verification of Vehicle Repair" procedure below.

NO
1) Substitute with a known-good "EMC coil" and check for proper operation. If the problem is corrected, replace "EMC coil" and then go to "Verification of Vehicle Repair" procedure below.

Verification of Vehicle Repair
1. Connect scan tool and select "Diagnostic Trouble Codes (DTCs)" mode.
2. Using scantool, Clear DTC.
3. Operate the vehicle within DTC Enable conditions in General information.
4. Are any DTCs present?

YES
1) Go to the applicable troubleshooting procedure.

NO
1) System performing to specification at this time.