Power Steering ECU Communication Stop Mode [11/2021 - ]: Procedure
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- CHECK FOR OPEN IN CAN BUS LINES (RACK AND PINION POWER STEERING GEAR ASSEMBLY MAIN LINE)
- Disconnect the cable from the negative (-) battery terminal.
- Disconnect the B66 rack and pinion power steering gear assembly connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition B66-10 (CANH) - B66-11 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω Result
Result OK NG
Result:
NG
REPAIR OR REPLACE CAN MAIN BUS LINES OR CONNECTOR (RACK AND PINION POWER STEERING GEAR ASSEMBLY)
Result:
OK
See step 2
- CHECK HARNESS AND CONNECTOR (POWER SOURCE CIRCUIT)
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition B66-7 (PGND) - Body ground Cable disconnected from negative (-) battery terminal Below 1 Ω - Reconnect the cable to the negative (-) battery terminal.
- Measure the voltage according to the value(s) in the table below.
Standard Voltage
Tester Connection Condition Specified Condition B66-8 (PIG) - Body ground Always 11 to 14 V Result
Result OK NG
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)
Result:
OK
See step 3
- Measure the resistance according to the value(s) in the table below.
- CHECK HARNESS AND CONNECTOR (POWER SOURCE CIRCUIT)
- Measure the voltage according to the value(s) in the table below.
Standard Voltage
Tester Connection Condition Specified Condition B66-4 (IG) - Body ground Ignition switch ON 10.5 to 16 V Result
Result OK NG
Result:
OK
REPLACE RACK AND PINION POWER STEERING GEAR ASSEMBLY. Refer to REMOVAL [11/2021 - 03/2024] , or refer to REMOVAL [03/2024 - ]
Result:
NG
GO TO STOP AND START SYSTEM (FOR BACKUP BOOST CONVERTER CIRCUIT). Refer to Backup Boost Converter Circuit [11/2021 - 03/2023] , or refer to Backup Boost Converter Circuit [03/2023 - ]
- Measure the voltage according to the value(s) in the table below.