Lexus RX (RX 350L, RX450h) 2016-2026 Repair Manual: Extension Module Malfunction 2 (B1556)

DESCRIPTION

This DTC is stored when a malfunction occurs in the Navigation ECU.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

B1556

Extension Module Malfunction 2

When any of the following conditions is met:

  • Internal power supply malfunction
  • Internal hard drive malfunction
  • EEPROM error
  • Storage malfunction

Navigation ECU

CAUTION / NOTICE / HINT

NOTICE:

Depending on the parts that are replaced during vehicle inspection or maintenance, performing initialization, registration or calibration may be needed. Refer to Precaution for Audio and Visual System.

Click here

PROCEDURE

1.

CHECK DTC

(a) Clear the DTCs.

Body Electrical > Navigation System > Clear DTCs

(b) Recheck for DTCs and check that no DTCs are output.

Body Electrical > Navigation System > Trouble Codes

OK:

No DTCs are output.

OK

USE SIMULATION METHOD TO CHECK

NG

REPLACE NAVIGATION ECU

    HD Radio Tuner Malfunction (B1551,B15A0,B15B3-B15B5,B15B7,B15F9)
    DESCRIPTION These DTCs are stored when a malfunction occurs in the radio receiver assembly. DTC No. Detection Item DTC Detection Condition Trouble Area B1551 HD Radio Tuner Malfunction ...

    Touch Pad Sensor Malfunction (B1559)
    DESCRIPTION This DTC is stored if the remote touch (remote operation controller assembly) detects a malfunction in itself, such as internal hardware failure or remote touch screen sensor malfunction. ...

    Other materials:

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    DESCRIPTION The main body ECU (multiplex network body ECU) controls the high beam headlights. WIRING DIAGRAM CAUTION / NOTICE / HINT NOTICE: Inspect the fuses for circuits related to this system before performing the following procedure. Before replacing the main body ECU (multiplex network bo ...

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    DESCRIPTION The front occupant classification sensor LH circuit consists of the occupant detection ECU and front occupant classification sensor LH. DTC B1780 is stored when a malfunction is detected in the front occupant classification sensor LH circuit. DTC No. Detection Item DTC Detection C ...

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

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

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