Lexus NX: Extension Module Malfunction 2 (B1556)

DESCRIPTION

These DTCs are 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 hard drive malfunction
  • EEPROM error
  • Storage malfunction

Navigation ECU

CAUTION / NOTICE / HINT

NOTICE:

When replacing the navigation ECU, always replace it with a new one.

If a navigation ECU which was installed to another vehicle is used, the following may occur:

  • A communication malfunction DTC may be stored.
  • The navigation ECU may not operate normally.

PROCEDURE

1.

CHECK DTC

(a) Clear the DTCs.

Click here

Body Electrical > Navigation System > Clear DTCs

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

Click here

Body Electrical > Navigation System > Trouble Codes

OK:

No DTCs are output.

OK

USE SIMULATION METHOD TO CHECK

NG

REPLACE NAVIGATION ECU

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DESCRIPTION This DTC is stored if the remote operation controller assembly (remote touch) detects a malfunction in itself, such as internal hardware failure or touch pad vibration driver malfunction.

 Touch Pad Memory Module Malfunction (B155B)

DESCRIPTION This DTC is stored if the remote operation controller assembly (remote touch) detects a malfunction in itself, such as internal hardware failure or touch pad memory module malfunction.

SEE MORE:

 Open in One Side of Bus 2 Branch Line

DESCRIPTION When the CAN bus main lines are normal (no open, short to ground, short to +B or short between lines) and there is an ECU or sensor on the "Communication Bus Check" screen that is indicated as not communicating or whose connection status on the "Communication Bus Check" screen changes in

 Removal

REMOVAL PROCEDURE 1. PRECAUTION Click here 2. CHECK FOR DTC (a) Check for DTCs. Click here NOTICE: Confirm that P0AA6 (Hybrid Battery Voltage System Isolation Fault) is not output before removing or installing an HV battery module. If this DTC is output, perform troubleshooting for this DTC firs

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