Mazda 2: M-MDS and Vehicle Not Communicating [Multiplex Communication System]

CAUTION:

• Perform the following on-board diagnosis according to FOREWORD [MULTIPLEX COMMUNICATION SYSTEM] troubleshooting procedure.

Detection Condition

• Possible causes of communication errors between the M-MDS and vehicle include communication circuit interruption due to an open circuit in the CAN communication wiring harness, or poor contact of connector terminals, or a BUS OFF condition due to a short circuit in the CAN communication wiring harness.

Possible Causes

• Open circuit in wiring harness between PCM and DLC-2
• Open circuit in BCM CAN line
• Improper insertion, connector terminal damage, deformation, corrosion, or disconnection of PCM, BCM, or connector C-03
• Short circuit in wiring harness between CAN system-related module CAN_L and CAN_H lines
• Short circuit to power supply in wiring harness between CAN system-related module
• Short circuit to ground in wiring harness between CAN system-related module
• Short circuit to power supply in CAN system-related module internal CAN lines
• Short circuit to ground in CAN system-related module internal CAN lines
• Damage, deformation, corrosion, or disconnection of DLC-2
• PCM power supply is not normal
• PCM ground is not normal
• PCM internal resistance is not normal
• CAN system-related module malfunction

Wiring Diagram

Diagnostic Procedure

CAUTION:

• When disconnecting the connector, verify that there is no looseness, damage, deformation, corrosion, or poor connection of the connector terminals.

DTC U0001:88, U0073:00

Diagnostic procedure

CAUTION:

• When disconnecting the connector, verify that there is no looseness, damage, deformation, corrosion, or poor connection of the connector terminals.

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