Lexus NX: Short in Motor Circuit (C1521-C1524,C1528,C1531-C1555)
DESCRIPTION
The power steering ECU assembly detects steering force using the signal received from the steering torque sensor, and also monitors the motor circuit for errors.
| 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 | On | Power switch on (IG) again | - |
| C1522 | Power Supply Sensor | Motor current sensor malfunction | Power steering ECU assembly | On | Power switch on (IG) again | - |
| C1523 | Current Deviation Excessive | Excessively large current deviation | Power steering ECU assembly | On | Power switch on (IG) again | - |
| C1524 | Motor Terminal Voltage | Short (or open) in motor circuit or abnormal voltage or current in motor circuit | Power steering ECU assembly | On | Power switch on (IG) again | - |
| C1528 | Motor Rotation Angle Sensor | Motor rotation angle sensor malfunction | Power steering ECU assembly | On | Power switch on (IG) again | - |
| C1531 | ECU Malfunction | ECU internal malfunction (CPU malfunction) | Power steering ECU assembly | On | Power switch on (IG) again | - |
| C1532 | ECU Malfunction | ECU internal malfunction (Peripheral circuit malfunction) | Power steering ECU assembly | On | Power switch on (IG) again | - |
| C1533 | Temperature Sensor Circuit is Low or High | ECU internal malfunction (Substrate temperature sensor malfunction) | Power steering ECU assembly | Off | After normal confirmation | - |
| C1534 | EEPROM | ECU internal malfunction (EEPROM error) | Power steering ECU assembly | Torque sensor zero point adjustment is set to the default value and control is continued. In this case, the warning light illuminates. | Power switch on (IG) again | - |
| C1555 | Motor Relay Welding Failure | Motor relay circuit malfunction | Power steering ECU assembly | On | Power 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.
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PROCEDURE
| 1. | CHECK FOR DTC |
(a) Clear the DTCs.
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(b) Check for DTCs.
Click here
| Result | Proceed to |
|---|---|
| DTCs (except C1521, C1522, C1523, C1524, C1528, C1531, C1532, C1533, C1534 and C1555 DTC) are not output. | A |
| DTCs (except C1521, C1522, C1523, C1524, C1528, C1531, C1532, C1533, C1534 and C1555 DTC) are output. | B |
| A | .gif) | REPLACE POWER STEERING ECU ASSEMBLY |
| B | | REPAIR CIRCUITS INDICATED BY OUTPUT DTCS |
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