Power Steering ECU Communication Stop Mode [08/2013 - ]: Procedure

WARNING: This page is about a different car, the 2014 Lexus ES 300h. However, it is still accessible from the selected car via links, so may be relevant.

CHECK FOR OPEN IN CAN BUS LINES (POWER STEERING ECU WITH MOTOR ASSEMBLY BRANCH LINE)

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

Disconnect the c1 power steering ECU with motor assembly connector.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

TEXT IN ILLUSTRATION

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

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

Standard Resistance

Tester Connection	Condition	Specified Condition
c1-7 (CANH) - c1-8 (CANL)	Cable disconnected from negative (-) auxiliary battery terminal	54 to 69 Ω

NG → REPAIR OR REPLACE CAN BRANCH LINE OR CONNECTOR (POWER STEERING ECU WITH MOTOR ASSEMBLY)

OK: Go to next step

CHECK HARNESS AND CONNECTOR (POWER SOURCE CIRCUIT)

Disconnect the c2 power steering ECU with motor assembly connector.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

Standard Resistance

Tester Connection	Condition	Specified Condition
c2-2 (PGND) - Body ground	Cable disconnected from negative (-) auxiliary battery terminal	Below 1 Ω

TEXT IN ILLUSTRATION

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

Connect the cable to the negative (-) auxiliary battery terminal.

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

Standard Voltage

Tester Connection	Condition	Specified Condition
c1-1 (IG) - Body ground	Power switch on (IG)	11 to 14 V

TEXT IN ILLUSTRATION

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

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)

OK → See step 3

REPLACE POWER STEERING ECU WITH MOTOR ASSEMBLY. Refer to REMOVAL [08/2013 - ]