Last Modified: 08-21-2023 6.11:8.1.0 Doc ID: RM100000001B6N6
Model Year Start: 2019 Model: Avalon HV Prod Date Range: [04/2018 -           ]
Title: POWER ASSIST SYSTEMS: POWER STEERING SYSTEM(for HV Model): C1581; Assist Map Number Un-Writing; 2019 - 2022 MY Avalon HV [04/2018 -        ]

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
  • Hybrid vehicle control ECU
  • Main body ECU (Multiplex network body ECU)
  • Skid control ECU (Brake booster with master cylinder assembly)
  • Rack and pinion power steering gear assembly

EPS warning light: Comes on

Assist Map Writing is performed or the power switch is turned on (IG) again

-

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 HV [04/2018 -        ]; POWER ASSIST SYSTEMS: POWER STEERING SYSTEM(for HV Model): CALIBRATION

HINT:

Related parts store information necessary for assist map writing.

Related Part:

  • Hybrid vehicle control ECU
  • Main body ECU (Multiplex network body ECU)
  • Skid control ECU (Brake booster with master cylinder assembly)

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 HV [04/2018 -        ]; NETWORKING: CAN COMMUNICATION SYSTEM (for HV 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

Hybrid vehicle control ECU

Main body ECU (Multiplex network body ECU)

Skid control ECU (Brake booster with master cylinder assembly)

NOTICE:

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

  • Hybrid vehicle control ECU

    Click here 2019 - 2021 MY Avalon HV [04/2018 - 08/2021]; HYBRID / BATTERY CONTROL: HYBRID VEHICLE CONTROL ECU: REMOVAL 2022 MY Avalon HV [08/2021 -        ]; HYBRID / BATTERY CONTROL: HYBRID VEHICLE CONTROL ECU: 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 booster with master cylinder assembly)

    Click here 2019 - 2021 MY Avalon HV [04/2018 - 08/2021]; BRAKE SYSTEM (OTHER): BRAKE BOOSTER (for HV Model): REMOVAL 2022 MY Avalon HV [08/2021 -        ]; BRAKE SYSTEM (OTHER): BRAKE BOOSTER (for HV Model): 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

GO TO DIAGNOSTIC PROCEDURE INDICATED BY OUTPUT DTC

B

REPLACE RACK AND PINION POWER STEERING GEAR ASSEMBLY 2019 - 2021 MY Avalon HV [04/2018 - 08/2021]; STEERING GEAR / LINKAGE: STEERING GEAR (for HV Model): REMOVAL 2022 MY Avalon HV [08/2021 -        ]; STEERING GEAR / LINKAGE: STEERING GEAR (for HV 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.

  • Hybrid vehicle control ECU

    Click here 2019 - 2021 MY Avalon HV [04/2018 - 08/2021]; HYBRID / BATTERY CONTROL: HYBRID VEHICLE CONTROL ECU: REMOVAL 2022 MY Avalon HV [08/2021 -        ]; HYBRID / BATTERY CONTROL: HYBRID VEHICLE CONTROL ECU: 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 booster with master cylinder assembly)

    Click here 2019 - 2021 MY Avalon HV [04/2018 - 08/2021]; BRAKE SYSTEM (OTHER): BRAKE BOOSTER (for HV Model): REMOVAL 2022 MY Avalon HV [08/2021 -        ]; BRAKE SYSTEM (OTHER): BRAKE BOOSTER (for HV Model): 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 2019 - 2021 MY Avalon HV [04/2018 - 08/2021]; STEERING GEAR / LINKAGE: STEERING GEAR (for HV Model): REMOVAL 2022 MY Avalon HV [08/2021 -        ]; STEERING GEAR / LINKAGE: STEERING GEAR (for HV Model): REMOVAL