Toyota Avalon (XX50) 2019-2022 Service & Repair Manual: Extension Module Malfunction 2 (B1556)

Toyota Avalon (XX50) 2019-2022 Service & Repair Manual / Audio, Visual, Telematics / Navigation / Multi Info Display / Navigation System(for Gasoline Model) / 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 power supply malfunction
  • 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.

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,B158D,B15A0,B15B0,B15B3,B15B7,B15BA,B15F9)

    Voice Recognition Microphone Disconnected (B1579)

    See More:

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