Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual: Assist Map Number Mismatch (C1582)

Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual / Suspension / Power Assist Systems / Power Steering System / Assist Map Number Mismatch (C1582)

DESCRIPTION

When an incorrect ECM, main body ECU (multiplex network body ECU) or skid control ECU (brake actuator assembly) is installed after the assist map has been written to the power steering ECU assembly, DTC C1582 is stored because the information stored in the power steering ECU assembly does not match the vehicle specifications.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Warning Indicate

Return-to-normal Condition

Note

C1582

Assist Map Number Mismatch

Assist map number mismatch
  • CAN communication system
  • Incorrect ECM
  • Incorrect main body ECU (multiplex network body ECU)
  • Incorrect skid control ECU (brake actuator assembly)
  • Power steering ECU assembly

EPS warning light: Does not come on

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

-

CAUTION / NOTICE / HINT

NOTICE:

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

Click here

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)

PROCEDURE

1.

CHECK CAN COMMUNICATION SYSTEM

(a) Check for DTCs.

Click here

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

2.

CHECK RELATED PART

(a) Check if the part below has been replaced with an incorrect part in the past.

Related Part

ECM

Main body ECU (Multiplex network body ECU)

Skid control ECU (Brake actuator assembly)

NOTICE:

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

  • ECM

    Click here

  • Main body ECU (Multiplex network body ECU)

    Click here

  • Skid control ECU (Brake actuator assembly)

    Click here

(b) When DTC C1582 is output and parts have not been exchanged, replace the power steering ECU assembly as it may have an internal malfunction.

NOTICE:

If the power steering ECU assembly has been replaced, perform assist map writing.

Click here

Result

Proceed to

The related part has an incorrect part number.

A

The related part has the correct part number, or a related part and power steering ECU assembly have not been replaced.

B
B

REPLACE POWER STEERING ECU ASSEMBLY

A

3.

REPLACE RELATED PART WITH PART THAT HAS CORRECT PART NUMBER

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

  • ECM

    Click here

  • Main body ECU (Multiplex network body ECU)

    Click here

  • Skid control ECU (Brake actuator assembly)

    Click here

NEXT

4.

CHECK FOR DTC

(a) Check for DTCs.

Click here

Chassis > EMPS > Trouble Codes

Result

Proceed to

DTCs are not output.

A

DTCs are output.

B
A

END
B

REPLACE POWER STEERING ECU ASSEMBLY

    Assist Map Number Un-Writing (C1581)
    DESCRIPTION This DTC will be stored if the power steering ECU assembly determines that the assist map is not written in the ECU. DTC No. Detection Item DTC Detection Condition Trouble Area ...

    Calibration
    CALIBRATION TORQUE SENSOR ZERO POINT CALIBRATION (USING TECHSTREAM) NOTICE: Perform torque sensor zero point calibration if any of the following conditions occur: The power steering ECU assembly ha ...

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    Lexus RX (RX 350L, RX450h) 2016-{YEAR} Owners Manual

    Lexus RX (RX 350L, RX450h) 2016-{YEAR} Repair Manual

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