Last Modified: 04-05-2023 6.11:8.1.0 Doc ID: RM100000001048O
Model Year Start: 2017 Model: Sienna Prod Date Range: [08/2016 -           ]
Title: POWER ASSIST SYSTEMS: POWER STEERING SYSTEM: U0100,U0129; Lost Communication with ECM; 2017 - 2020 MY Sienna [08/2016 -        ]

DTC

U0100

Lost Communication with ECM

DTC

U0129

Lost Communication with Brake System Control Module

DESCRIPTION

The power steering ECU receives signals from the ECM and the skid control ECU via the CAN communication system.

DTC No.

DTC Detection Condition

Trouble Area

U0100

ECM communication error
  • CAN communication system
  • ECM

U0129

Skid control ECU communication error
  • CAN communication system
  • Brake actuator assembly (Skid control ECU)

HINT:

When two or more DTCs starting with [U] are output simultaneously, inspect the connectors and wire harness of each ECU.

PROCEDURE

1.

RECONFIRM DTC

(a) Clear the DTCs (See page 2016 - 2020 MY Sienna [12/2015 -        ]; POWER ASSIST SYSTEMS: POWER STEERING SYSTEM: DTC CHECK / CLEAR ).

(b) Check for DTCs.

OK:

DTC U0100 or U0129 is not output.

OK

CHECK FOR INTERMITTENT PROBLEMS

NG

GO TO CAN COMMUNICATION SYSTEM

(See page 2017 MY Sienna [08/2016 - 11/2017]; NETWORKING: CAN COMMUNICATION SYSTEM: HOW TO PROCEED WITH TROUBLESHOOTING 2018 - 2020 MY Sienna [11/2017 -        ]; NETWORKING: CAN COMMUNICATION SYSTEM: HOW TO PROCEED WITH TROUBLESHOOTING )