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Initial Inspection and Diagnostic Overview

Procedures For Determining the Location of A Malfunction [MULTIPLEX COMMUNICATION SYSTEM]

System Wiring Diagram

System Wiring Diagram:






PCM
1. Inspect the display of DTC U0101, U0121 and/or U0155, using the M-MDS. (See DTC TABLE [MULTIPLEX COMMUNICATION SYSTEM].) Diagnostic Trouble Code Descriptions
2. Referring to the following table, determine the malfunctioning part of the CAN system.






TCM
1. Inspect the display of DTC U0100, U0121, U0140 and/or U0415 using the M-MDS. (See DTC TABLE [MULTIPLEX COMMUNICATION SYSTEM].) Diagnostic Trouble Code Descriptions
2. Referring to the following table, determine the malfunctioning part of the CAN system.






DSC HU/CM
1. Inspect the display of DTC U0100, U0101, U0114, U0140, U1900 and/or U2023 using the M-MDS. (See DTC TABLE [MULTIPLEX COMMUNICATION SYSTEM].) Diagnostic Trouble Code Descriptions

CAUTION: DTC U2023 may not be cleared during engine starting even if DTC clearing is done using the WIMPS. When clearing DTC U2023, execute with the ignition switch in the ON position (Engine off).

NOTE: You may want to check which unit is malfunctioning according to Freeze Frame Data. "Electrical" > "IC Service Function" > "Freeze Frame Data".This function is supported on IDS, not PDS.

2. Referring to the following table, determine the malfunctioning part of the CAN system.






AWD Control Module
1. Inspect the display of DTC U0100, U0101, U0121 and/or U0155 using the M-MDS. (See DTC TABLE [MULTIPLEX COMMUNICATION SYSTEM].) Diagnostic Trouble Code Descriptions
2. Referring to the following table, determine the malfunctioning part of the CAN system.






BCM

NOTE: There is no DTC in the BCM that determines signal quality between it and the other module. Due to this, determine the malfunction location using the DTC on the other module side.

1. Referring to the following table, determine the malfunctioning part of the CAN system.






SAS Control Module
1. Inspect the display of DTC U0155 using the M-MDS. (See DTC TABLE [MULTIPLEX COMMUNICATION SYSTEM].) Diagnostic Trouble Code Descriptions
2. Referring to the following table, determine the malfunctioning part of the CAN system.






Keyless Control Module
1. Inspect the display of DTC U0100, U0140, U0323 and/or U2023 using the M-MDS. (See DTC TABLE [MULTIPLEX COMMUNICATION SYSTEM].) Diagnostic Trouble Code Descriptions

CAUTION: DTC U2023 may not be cleared during engine starting even if DTC clearing is done using the M-MDS. When clearing DTC U2023, execute with the ignition switch in the ON position (Engine off).

NOTE: You may want to check which unit is malfunctioning according to Freeze Frame Data. "Electrical" > "IC Service Function" > "Freeze Frame Data".This function is supported on IDS, not PDS.

2. Referring to the following table, determine the malfunctioning part of the CAN system.






Instrument Cluster
1. Inspect the display of DTC U0100, U0101, U0114, U0121, U0140, U0151 and/or U0214 using the M-MDS. (See DTC TABLE [MULTIPLEX COMMUNICATION SYSTEM].) Diagnostic Trouble Code Descriptions
2. Referring to the following table, determine the malfunctioning part of the CAN system.






NOTE: There is no DTC in the instrument cluster that determines signal quality between it and the information display. Due to this, determine the malfunction location using the DTC on the information display.

3. Inspect the display of DTC U0164 using the M-MDS. (See DTC TABLE [MULTIPLEX COMMUNICATION SYSTEM].) Diagnostic Trouble Code Descriptions
4. Referring to the following table, determine the malfunctioning part of the CAN system.






Climate Control Unit

NOTE: There is no DTC in the climate control unit that determines signal quality between it and the information display. Due to this, determine the malfunction location using the DTC on the information display.

1. Inspect the display of DTC U0155 using the M-MDS. (See DTC TABLE [MULTIPLEX COMMUNICATION SYSTEM].) Diagnostic Trouble Code Descriptions
2. Referring to the following table, determine the malfunctioning part of the CAN system.






Car-navigation Unit/Audio Unit (Base Module)

NOTE: There is no DTC in the car-navigation unit/audio unit (base module) that determines signal quality between it and the information display. Due to this, determine the malfunction location using the DTC on the information display.

1. Referring to the following table, determine the malfunctioning part of the CAN system.






Information display
1. Inspect the display of DTC U0166, U0181 and/or U0184 using the input/output check mode.
2. Referring to the following table, determine the malfunctioning part of the CAN system.






Repair Procedure
1. Inspect the connector of malfunctioning module.
- If there is any malfunction, repair or replace the connector.

2. Inspect the malfunctioning wiring harnesses as follow:
- If there is any malfunction, repair or replace the wiring harnesses.
- If there is no malfunction, replace the malfunctioning module.
- Short to GND
- Short to power supply
- Twisted pair short each other
- Open circuit

3. Make sure to reconnect all disconnected connectors.
4. Clear the CAN system related DTCs using the M-MDS.
5. Verify if the CAN system related DTCs are displayed using the M-MDS.
- If the same following DTCs are present, replace the malfunctioning module.
- U0073 (PCM, TCM, DSC HU/CM, AWD control module, BCM, SAS control module, keyless control module, instrument cluster)
- U0516 (Climate control unit)
- U2516 (Instrument cluster, information display)
- 16:Er12 (Audio unit (base module))

- If other DTC is present, perform the appropriate DTC inspection. (See DTC TABLE [MULTIPLEX COMMUNICATION SYSTEM].) Diagnostic Trouble Code Descriptions
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