Last Modified: 08-21-2023 6.11:8.1.0 Doc ID: RM100000001AZ9L
Model Year Start: 2019 Model: Avalon Prod Date Range: [04/2018 - 08/2021]
Title: BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: ELECTRONICALLY CONTROLLED BRAKE SYSTEM (for Gasoline Model): C1231; Steering Angle Sensor Circuit; 2019 - 2021 MY Avalon [04/2018 - 08/2021]

DTC

C1231

Steering Angle Sensor Circuit

DESCRIPTION

The skid control ECU (brake actuator assembly) receives steering angle sensor signals via CAN communication. When a malfunction occurs in the communication line with the steering angle sensor, DTC U0126 (Lost Communication With Steering Angle Sensor Module) is stored.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

C1231

Steering Angle Sensor Circuit

While steering angle sensor communication is enabled, a malfunction signal output is received during the sensor self check (sensor malfunction).

Steering angle sensor internal malfunction

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

Inspect the fuses for circuits related to this system before performing the following procedure.

HINT:

  • When U0126 is output together with C1231, inspect and repair the trouble areas indicated by U0126 first.

    Click here 2019 - 2021 MY Avalon [04/2018 - 08/2021]; BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: ELECTRONICALLY CONTROLLED BRAKE SYSTEM (for Gasoline Model): U0073,U0100,U0123,U0126,U0142,U0151; Control Module Communication Bus Off

  • When a speed sensor or yaw rate and acceleration sensor (airbag sensor assembly) is malfunctioning, DTCs for the steering angle sensor may be output even when the steering angle sensor is normal. When DTCs for a speed sensor or the yaw rate and acceleration sensor (airbag sensor assembly) are output together with DTCs for the steering angle sensor, inspect and repair the speed sensor and yaw rate and acceleration sensor (airbag sensor assembly) first, and then inspect and repair the steering angle sensor.

PROCEDURE

1.

CHECK DTC

(a) Clear the DTCs.

Chassis > ABS/VSC/TRAC/EPB > Clear DTCs

(b) Turn the engine switch off.

(c) Turn the engine switch on (IG) again and check that no CAN communication system DTCs are output.

Click here 2019 - 2022 MY Avalon [04/2018 -        ]; NETWORKING: CAN COMMUNICATION SYSTEM (for Gasoline Model): HOW TO PROCEED WITH TROUBLESHOOTING

(d) Drive the vehicle at a speed of 35 km/h (22 mph), turn the steering wheel to the right and left, and check that no speed sensor and/or yaw rate and acceleration sensor DTCs are output.

Chassis > ABS/VSC/TRAC/EPB > Trouble Codes

Result

Proceed to

C1231 is output

A

CAN communication system DTCs are output

B

Speed sensor and/or yaw rate and acceleration sensor DTCs are output

C

C1231 is not output

D

HINT:

  • When CAN communication system DTCs are output, repair the CAN communication system before repairing each corresponding sensor.
  • If there is a malfunction in a speed sensor or the yaw rate and acceleration sensor (airbag sensor assembly), an abnormal value may be output even though the steering angle sensor is normal.
  • If speed sensor and yaw rate and acceleration sensor DTCs are output simultaneously, repair the sensors and inspect the steering angle sensor.
B

INSPECT CAN COMMUNICATION SYSTEM

C

REPAIR CIRCUITS INDICATED BY OUTPUT DTCS 2019 - 2020 MY Avalon [04/2018 - 08/2020]; BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: ELECTRONICALLY CONTROLLED BRAKE SYSTEM (for Gasoline Model): DIAGNOSTIC TROUBLE CODE CHART 2021 MY Avalon [08/2020 - 08/2021]; BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: ELECTRONICALLY CONTROLLED BRAKE SYSTEM (for Gasoline Model): DIAGNOSTIC TROUBLE CODE CHART

D

USE SIMULATION METHOD TO CHECK

A

2.

CHECK HARNESS AND CONNECTOR (POWER SOURCE TERMINAL)

(a) Turn the engine switch off.

*a

Front view of wire harness connector

(to Steering Angle Sensor)

(b) Remove the steering wheel and column cover.

(c) Make sure that there is no looseness at the locking part and the connecting part of the connector.

OK:

The connector is securely connected.

(d) Disconnect the G48 steering angle sensor connector.

(e) Check both the connector case and the terminals for deformation and corrosion.

OK:

No deformation or corrosion.

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

Standard Voltage:

Tester Connection

Condition

Specified Condition

G48-9 (IG1) - Body ground

Engine switch on (IG)

11 to 14 V

G48-4 (BAT) - Body ground

Always

11 to 14 V
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)
OK

3.

CHECK HARNESS AND CONNECTOR (GROUND TERMINAL)

(a) Turn the engine switch off.

*a

Front view of wire harness connector

(to Steering Angle Sensor)

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

NOTICE:

Before measuring the resistance of the steering angle sensor, turn the engine switch off and leave the vehicle for 1 minute or more without operating the key or switches, or opening or closing the doors.

Standard Resistance:

Tester Connection

Condition

Specified Condition

G48-6 (ESS) - Body ground

1 minute after engine switch off

Below 1 Ω
OK

REPLACE STEERING ANGLE SENSOR

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR (GROUND CIRCUIT)