DETERMINING OPEN CIRCUIT LOCATION (MS-CAN)

2016 – MX-5 – Multiplex Communication System

DETERMINING OPEN CIRCUIT LOCATION (MS-CAN)

CAUTION:

Perform the following malfunction diagnosis only when it is diagnosed with a open circuit by CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW. (See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW.)
If the malfunctioning part is detected in the communication line, before disconnecting the related connector for inspection, press the connector in the connection direction to verify that there is no looseness or disconnection.
When disconnecting the connector, verify that there is no damage, deformation, or corrosion of the connector terminals.

1. Verify DTCs of the modules related to the CAN system.

2. Apply the communication error DTC and the failed module to DTC output pattern and malfunctioning location, and select the possible cause for the diagnostic result and the reference for the inspection item. (See DTC Output Pattern And Malfunctioning Location.)

NOTE:

The open circuit location can be determined by the DTC indicated in the DTC output pattern and malfunctioning location chart. DTCs not listed in the chart are not used for the determination of the open circuit location. (See DTC Output Pattern And Malfunctioning Location.)

3. Inspect the possible cause and inspection item of the applicable malfunctioning part.

4. After repairs, return to CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW, and verify that the repairs have been completed. (See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW.)

DTC Output Pattern And Malfunctioning Location

Cross (×): Communication error-related DTC and failed module

M-MDS display		DTC output pattern and malfunctioning location
DTC output module	DTC	DTC output pattern and malfunctioning location
IC (Instrument cluster)	U0232:00		×	×
BSM^*1 (Blind spot monitoring (BSM) control module (LH))	U0100:00	×
	U0121:00	×
	U0155:00	×
	U0214:00	×
EATC (Climate control unit)	U0155:00	×
M-MDS display module		[Fail] display pattern
IC		×
BSM^*1			×	×
EATC			×		×
Diagnostic result
Possible cause and inspection item		A	B	C	D

*1: With blind spot monitoring (BSM) system

A

Possible cause

Connector terminal disconnection, poor contact, damage, deformation, corrosion
Instrument cluster power supply voltage or body ground malfunction
Open circuit in wiring harness between instrument cluster and branch A
Instrument cluster malfunction

System wiring diagram

Inspection item

Instrument cluster power supply voltage-related wiring harness and fuse
Instrument cluster body ground related wiring harness
Instrument cluster connector
Wiring harness between instrument cluster terminal C and branch A
Wiring harness between instrument cluster terminal E and branch A
Instrument cluster

B

With blind spot monitoring (BSM) system

Possible cause

Connector terminal disconnection, poor contact, damage, deformation, corrosion
Open circuit in wiring harness between branch A and connector C-14
Open circuit in wiring harness between connector C-14 and branch B
Connector C-14 malfunction

System wiring diagram

Inspection item

Connector C-14
Wiring harness between branch A and connector C-14
Wiring harness between connector C-14 and branch B

Without blind spot monitoring (BSM) system

Possible cause

Connector terminal disconnection, poor contact, damage, deformation, corrosion
Climate control unit power supply voltage or body ground malfunction
Open circuit in wiring harness between branch A and connector C-14
Open circuit in wiring harness between connector C-14 and connector C-14
Open circuit in wiring harness between connector C-14 and climate control unit
Connector C-14 malfunction
Climate control unit malfunction

System wiring diagram

Inspection item

Climate control unit power supply voltage-related wiring harness and fuse
Climate control unit body ground related wiring harness
Climate control unit connector
Connector C-14
Wiring harness between branch A and connector C-14
Wiring harness between connector C-14 and connector C-14
Wiring harness between climate control unit terminal D and connector C-14
Wiring harness between climate control unit terminal B and connector C-14
Climate control unit

C