Last Modified: 08-21-2023 6.11:8.1.0 Doc ID: RM100000001RDMX
Model Year Start: 2021 Model: Avalon Prod Date Range: [08/2020 -           ]
Title: POWER ASSIST SYSTEMS: POWER STEERING SYSTEM (for Gasoline Model): C1581; Assist Map Number Un-Writing; 2021 - 2022 MY Avalon [08/2020 -        ]

DTC

C1581

Assist Map Number Un-Writing

DESCRIPTION

This DTC will be stored if the power steering ECU (rack and pinion power steering gear assembly) determines that the assist map is not written in the ECU.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Warning Indicate

Return-to-normal Condition

Note

C1581

Assist Map Number Un-Writing

Assist map not written in power steering ECU (rack and pinion power steering gear assembly)

  • CAN communication system
  • ECM
  • Main body ECU (Multiplex network body ECU)
  • Skid control ECU (Brake actuator assembly)
  • AVS ECU (Absorber control ECU) (w/ Adaptive Variable Suspension System)
  • Rack and pinion power steering gear assembly

EPS warning light: Comes on

Assist Map Writing is performed

-

CAUTION / NOTICE / HINT

NOTICE:

If the rack and pinion power steering gear assembly has been replaced, perform assist map writing and torque sensor zero point calibration.

Click here 2019 - 2022 MY Avalon [04/2018 -        ]; POWER ASSIST SYSTEMS: POWER STEERING SYSTEM (for Gasoline Model): CALIBRATION

HINT:

Related parts store information necessary for assist map writing.

Related Part:

  • ECM
  • Main body ECU (Multiplex network body ECU)
  • Skid control ECU (Brake actuator assembly)
  • AVS ECU (Absorber control ECU) (w/ Adaptive Variable Suspension System)

PROCEDURE

1.

PERFORM ASSIST MAP WRITING

(a) Perform assist map writing.

Chassis > EMPS > Utility

Tester Display

Signal Check

(b) Check for DTCs.

Chassis > EMPS > Trouble Codes

Result

Proceed to

DTC C1581 is output.

A

DTC C1581 is not output.

B

B

END

A

2.

CHECK CAN COMMUNICATION SYSTEM

(a) Check for DTCs.

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

Result

Proceed to

CAN communication system DTCs are not output.

A

CAN communication system DTCs are output.

B

B

GO TO CAN COMMUNICATION SYSTEM

A

3.

CHECK RELATED PART

(a) Confirm if the related part has the correct part number.

Related Part

ECM

Main body ECU (Multiplex network body ECU)

Skid control ECU (Brake actuator assembly)

AVS ECU (Absorber control ECU) (w/ Adaptive Variable Suspension System)

NOTICE:

When removing the related part to check it, be sure to follow the appropriate procedures and precautions.

  • ECM

    for 2GR-FKS: Click here 2019 - 2021 MY Avalon [04/2018 - 08/2021]; 2GR-FKS (ENGINE CONTROL): ECM: REMOVAL 2022 MY Avalon [08/2021 -        ]; 2GR-FKS (ENGINE CONTROL): ECM: REMOVAL

    for A25A-FKS: Click here 2021 - 2022 MY Avalon [08/2020 -        ]; A25A-FKS (ENGINE CONTROL): ECM: REMOVAL

  • Main body ECU (Multiplex network body ECU)

    Click here 2019 - 2021 MY Avalon Avalon HV [04/2018 - 08/2021]; POWER DISTRIBUTION: MAIN BODY ECU: REMOVAL 2022 MY Avalon Avalon HV [08/2021 -        ]; POWER DISTRIBUTION: MAIN BODY ECU: REMOVAL

  • Skid control ECU (Brake actuator assembly)

    Click here 2021 MY Avalon [08/2020 - 08/2021]; BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: BRAKE ACTUATOR (for Gasoline Model): REMOVAL 2022 MY Avalon [08/2021 -        ]; BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: BRAKE ACTUATOR (for Gasoline Model): REMOVAL

  • AVS ECU (Absorber control ECU) (w/ Adaptive Variable Suspension System)

    Click here 2019 - 2021 MY Avalon Avalon HV [04/2018 - 08/2021]; SUSPENSION CONTROL: SUSPENSION CONTROL ECU: REMOVAL 2022 MY Avalon Avalon HV [08/2021 -        ]; SUSPENSION CONTROL: SUSPENSION CONTROL ECU: REMOVAL

Result

Proceed to

The related part has the correct part number.

A

The related part has an incorrect part number.

B

B

GO TO STEP 5

A

4.

CHECK FOR DTC

(a) Select Health Check on the Techstream screen and check if system DTCs of the related part are output.

HINT:

If system DTCs of the related part are stored, assist map writing to the power steering ECU (rack and pinion power steering gear assembly) may not be performed properly.

Result

Proceed to

System DTCs of the related part are output.

A

System DTCs of the related part are not output.

B

A

REPAIR CIRCUIT INDICATED BY OUTPUT CODE

B

REPLACE RACK AND PINION POWER STEERING GEAR ASSEMBLY 2021 MY Avalon [08/2020 - 08/2021]; STEERING GEAR / LINKAGE: STEERING GEAR (for Gasoline Model): REMOVAL 2022 MY Avalon [08/2021 -        ]; STEERING GEAR / LINKAGE: STEERING GEAR (for Gasoline Model): REMOVAL

5.

REPLACE RELATED PART WITH PART THAT HAS CORRECT PART NUMBER

(a) Replace the related part with one that has the correct part number.

  • ECM

    for 2GR-FKS: Click here 2019 - 2021 MY Avalon [04/2018 - 08/2021]; 2GR-FKS (ENGINE CONTROL): ECM: REMOVAL 2022 MY Avalon [08/2021 -        ]; 2GR-FKS (ENGINE CONTROL): ECM: REMOVAL

    for A25A-FKS: Click here 2021 - 2022 MY Avalon [08/2020 -        ]; A25A-FKS (ENGINE CONTROL): ECM: REMOVAL

  • Main body ECU (Multiplex network body ECU)

    Click here 2019 - 2021 MY Avalon Avalon HV [04/2018 - 08/2021]; POWER DISTRIBUTION: MAIN BODY ECU: REMOVAL 2022 MY Avalon Avalon HV [08/2021 -        ]; POWER DISTRIBUTION: MAIN BODY ECU: REMOVAL

  • Skid control ECU (Brake actuator assembly)

    Click here 2021 MY Avalon [08/2020 - 08/2021]; BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: BRAKE ACTUATOR (for Gasoline Model): REMOVAL 2022 MY Avalon [08/2021 -        ]; BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: BRAKE ACTUATOR (for Gasoline Model): REMOVAL

  • AVS ECU (Absorber control ECU) (w/ Adaptive Variable Suspension System)

    Click here 2019 - 2021 MY Avalon Avalon HV [04/2018 - 08/2021]; SUSPENSION CONTROL: SUSPENSION CONTROL ECU: REMOVAL 2022 MY Avalon Avalon HV [08/2021 -        ]; SUSPENSION CONTROL: SUSPENSION CONTROL ECU: REMOVAL

NEXT

6.

CHECK FOR DTC

(a) Check for DTCs.

Chassis > EMPS > Trouble Codes

Result

Proceed to

DTCs are not output.

A

DTCs are output.

B

A

END

B

REPLACE RACK AND PINION POWER STEERING GEAR ASSEMBLY 2021 MY Avalon [08/2020 - 08/2021]; STEERING GEAR / LINKAGE: STEERING GEAR (for Gasoline Model): REMOVAL 2022 MY Avalon [08/2021 -        ]; STEERING GEAR / LINKAGE: STEERING GEAR (for Gasoline Model): REMOVAL