Toyota Yaris: Can Communication System / ECM Communication Stop Mode

Toyota Yaris XP210 (2020-2026) Reapir and Service Manual / Power Source & Network / Networking / Can Communication System / ECM Communication Stop Mode

DESCRIPTION

Detection Item	Symptom	Trouble Area
ECM Communication Stop Mode	Communication stop for "ECM (Engine)" is indicated on the "Communication Bus Check" screen of the GTS. Click here	ECM main line or connector Power source circuit of ECM ECM ground circuit ECM

Detection Item

Symptom

Trouble Area

ECM Communication Stop Mode

Communication stop for "ECM (Engine)" is indicated on the "Communication Bus Check" screen of the GTS.

Click here

ECM main line or connector
Power source circuit of ECM
ECM ground circuit
ECM

WIRING DIAGRAM

CAUTION / NOTICE / HINT

CAUTION:

When performing the confirmation driving pattern, obey all speed limits and traffic laws.

NOTICE:

Because the order of diagnosis is important to allow correct diagnosis, make sure to begin troubleshooting using How to Proceed with Troubleshooting when CAN communication system related DTCs are output.
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Before measuring the resistance of the CAN bus, turn the ignition switch off and leave the vehicle for 1 minute or more without operating the key or any switches, or opening or closing the doors. After that, disconnect the cable from the negative (-) auxiliary battery terminal and leave the vehicle for 1 minute or more before measuring the resistance.
After the ignition switch is turned off, there may be a waiting time before disconnecting the negative (-) auxiliary battery terminal.
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When disconnecting and reconnecting the auxiliary battery, there is an automatic learning function that completes learning when the respective system is used.
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Some parts must be initialized and set when replacing or removing and installing parts.
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After performing repairs, perform the DTC check procedure and confirm that the DTCs are not output again.
DTC check procedure: Turn the ignition switch to ON and wait for 1 minute or more. Then operate the suspected malfunctioning system and drive the vehicle at 60 km/h (37 mph) or more for 5 minutes or more.
After the repair, perform the CAN bus check and check that all the ECUs and sensors connected to the CAN communication system are displayed as normal.
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Inspect the fuses for circuits related to this system before performing the following procedure.
Before replacing the ECM, refer to Registration.
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HINT:

Before disconnecting related connectors for inspection, push in on each connector body to check that the connector is not loose or disconnected.
When a connector is disconnected, check that the terminals and connector body are not cracked, deformed or corroded.

PROCEDURE

1.	CHECK FOR OPEN IN CAN BUS LINES (ECM MAIN LINE)

(a) Disconnect the cable from the negative (-) auxiliary battery terminal.

(b) Disconnect the ECM connector.

Standard Resistance:

Tester Connection	Condition	Specified Condition
A106-8 (CANH) - A106-18 (CANL)	Cable disconnected from negative (-) auxiliary battery terminal	108 to 132 Ω

*a	Front view of wire harness connector (to ECM)

REPAIR OR REPLACE CAN MAIN BUS LINES OR CONNECTOR (ECM)

2.	CHECK ECM POWER SOURCE CIRCUIT

(a) Check the ECM power source circuit.

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REPLACE ECM

REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)

Steering Angle Sensor Communication Stop Mode

DESCRIPTION Detection Item Symptom Trouble Area Steering Angle Sensor Communication Stop Mode Communication stop for "Spiral cable (Steering Angle Sensor)" is indicated on the "Communication Bus Check" screen of the GTS...

Main Body ECU Communication Stop Mode

DESCRIPTION Detection Item Symptom Trouble Area Main Body ECU Communication Stop Mode Communication stop for "Main Body" is indicated on the "Communication Bus Check" screen of the GTS...

Other information:

Toyota Yaris XP210 (2020-2026) Reapir and Service Manual: Lost Communication with Steering Angle Sensor Module Missing Message (U012687,U010087,U012987,U014087,U023A87)

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DESCRIPTION The condition of the windshield wiper switch assembly is detected and sent to the steering sensor in this circuit. WIRING DIAGRAM CAUTION / NOTICE / HINT NOTICE: If the main body ECU (multiplex network body ECU) is replaced, refer to the Registration...