Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual: Short in Motor Circuit (C1521-C1523,C1528,C1531-C1555)

Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual / Steering / Power Assist Systems / Power Steering System / Short in Motor Circuit (C1521-C1523,C1528,C1531-C1555)

DESCRIPTION

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Warning Indicate

Return-to-normal Condition

Note

C1521

Short in Motor Circuit

Motor overcurrent

Power steering ECU assembly

EPS warning light: Comes on

Engine switch on (IG) again

-

C1522

Power Supply Sensor

Motor current sensor malfunction

Power steering ECU assembly

EPS warning light: Comes on

Engine switch on (IG) again

-

C1523

Current Deviation Excessive

Excessively large current deviation

Power steering ECU assembly

EPS warning light: Comes on

Engine switch on (IG) again

-

C1528

Motor Rotation Angle Sensor

Motor rotation angle sensor malfunction

Power steering ECU assembly

EPS warning light: Comes on

Engine switch on (IG) again

-

C1531

ECU Malfunction

ECU internal malfunction

(CPU malfunction)

Power steering ECU assembly

EPS warning light: Comes on

The ECU judges the system has returned to normal or the power switch is turned on (IG) again

-

C1532

ECU Malfunction

ECU internal malfunction

(Peripheral circuit malfunction)

Power steering ECU assembly

EPS warning light: Comes on

Engine switch on (IG) again

-

C1533

Temperature Sensor Circuit is Low or High

ECU internal malfunction

(Substrate temperature sensor malfunction)

Power steering ECU assembly

EPS warning light: Comes on

Engine switch on (IG) again

-

C1534

EEPROM

ECU internal malfunction

(EEPROM error)

Power steering ECU assembly

EPS warning light: Comes on

Engine switch on (IG) again

-

C1555

Motor Relay Welding Failure

Motor relay circuit malfunction

Power steering ECU assembly

EPS Warning Light: Comes on

Engine switch 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

PROCEDURE

1.

CHECK FOR DTC

(a) Clear the DTCs.

Click here

Chassis > EMPS > Clear DTCs

(b) Check for DTCs.

Click here

Chassis > EMPS > Trouble Codes

Result

Proceed to

DTCs other than C1521, C1522, C1523, C1528, C1531, C1532, C1533, C1534 or C1555 are not output.

A

DTCs other than C1521, C1522, C1523, C1528, C1531, C1532, C1533, C1534 or C1555 are output.

B

A

REPLACE POWER STEERING ECU ASSEMBLY

B

GO TO DIAGNOSTIC TROUBLE CODE CHART

    Torque Sensor Zero Point Adjustment Incomplete (C1516)
    DESCRIPTION This DTC does not indicate a malfunction. The power steering ECU assembly stores this DTC when it determines that torque sensor zero point calibration has not completed. DTC No. Detec ...

    Vehicle Speed Signal (C1541)
    DESCRIPTION The power steering ECU assembly receives vehicle speed signals from the skid control ECU (brake actuator assembly) via CAN communication. The ECU provides appropriate assist force in accor ...

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