Toyota Yaris: Can Communication System / Power Steering ECU Communication Stop Mode

Toyota Yaris XP210 (2020-2025) Reapir and Service Manual / Power Source & Network / Networking / Can Communication System / Power Steering ECU Communication Stop Mode

DESCRIPTION

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

Detection Item

Symptom

Trouble Area

Power Steering ECU Communication Stop Mode

Communication stop for "Power Steering (EPS)" is indicated on the "Communication Bus Check" screen of the GTS.

Click here

Power steering ECU assembly main line or connector
Power source circuit of power steering ECU assembly
Power steering ECU assembly ground circuit
Power steering ECU assembly

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.
Click here
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.
Click here
When disconnecting and reconnecting the auxiliary battery, there is an automatic learning function that completes learning when the respective system is used.
Click here
Some parts must be initialized and set when replacing or removing and installing parts.
Click here
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.
Click here

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 (POWER STEERING ECU ASSEMBLY MAIN LINE)

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

(b) Disconnect the power steering ECU assembly connector.

Standard Resistance:

Tester Connection	Condition	Specified Condition
H1-7 (CANH) - H1-8 (CANL)	Cable disconnected from negative (-) auxiliary battery terminal	108 to 132 Ω

*a	Front view of wire harness connector (to Power Steering ECU Assembly)

REPAIR OR REPLACE CAN MAIN BUS LINES OR CONNECTOR (POWER STEERING ECU ASSEMBLY)

2.	CHECK HARNESS AND CONNECTOR (POWER SOURCE CIRCUIT)

(a) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection	Condition	Specified Condition
H2-2 (PGND) - Body ground	Cable disconnected from negative (-) auxiliary battery terminal	Below 1 Ω

*a	Front view of wire harness connector (to Power Steering ECU Assembly)

REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)

3.	CHECK HARNESS AND CONNECTOR (POWER SOURCE CIRCUIT)

(a) Reconnect the cable to the negative (-) auxiliary battery terminal.

(b) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection	Condition	Specified Condition
H1-1 (IG) - Body ground	Ignition switch ON	10.5 to 16 V

*a	Front view of wire harness connector (to Power Steering ECU Assembly)

REPLACE POWER STEERING ECU ASSEMBLY

GO TO STOP AND START SYSTEM (BACKUP BOOST CONVERTER CIRCUIT)

Air Conditioning Amplifier Communication Stop Mode

DESCRIPTION Detection Item Symptom Trouble Area Air Conditioning Amplifier Communication Stop Mode Communication stop for "Air Conditioning Amplifier" is indicated on the "Communication Bus Check" screen of the GTS...

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...

Other information:

Toyota Yaris XP210 (2020-2025) Reapir and Service Manual: Lost Communication With ECM/PCM "A" Missing Message (U010087,U011487,U012987,U013187,U014087,U015187,U016887,U023587,U023A87,U111287,U113387)

DESCRIPTION The combination meter assembly communicates with each ECU via CAN communication. DTC No. Detection Item DTC Detection Condition Trouble Area U010087 Lost Communication With ECM/PCM "A" Missing Message Diagnosis Condition: The ignition switch is ON IG power source voltage is 9...

Toyota Yaris XP210 (2020-2025) Reapir and Service Manual: Repair

REPAIR PROCEDURE 1. REPAIR INTAKE VALVE SEAT NOTICE: While repairing the intake valve seat, make sure to constantly check the valve seat width and valve seating position. Release the cutter gradually to make the intake valve seat smooth. (a) Using a 45° cutter, resurface the intake valve seat so that the intake valve seat width is more than the standard...