Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual: Lost Communication with Sliding Sunshade ECU (B2329)

Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual / Power Source & Network / Networking / Lin Communication System / Lost Communication with Sliding Sunshade ECU (B2329)

DESCRIPTION

This DTC is stored when LIN communication between the roof sunshade ECU (sliding roof drive gear assembly) and main body ECU (multiplex network body ECU) stops for 10 seconds or more.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

B2329

Lost Communication with Sliding Sunshade ECU

No communication between roof sunshade ECU (sliding roof drive gear assembly) and main body ECU (multiplex network body ECU) for 10 seconds or more.
  • Roof sunshade ECU (sliding roof drive gear assembly)
  • Main body ECU (multiplex network body ECU)
  • Instrument panel junction block assembly
  • Wire harness or connector
  • S/ROOF NO. 2 fuse

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 body ECU), refer to Registration.

    Click here

  • When the roof sunshade ECU (sliding roof drive gear sub-assembly) is replaced or removed and reinstalled, it is necessary to perform initialization.

    Click here

PROCEDURE

1.

INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

(a) Remove the instrument panel junction block assembly.

Click here

*a

Component without harness connected

(Instrument Panel Junction Block Assembly)

-

-

(b) Remove the main body ECU (multiplex network body ECU) from the instrument panel junction block assembly.

(c) Measure the resistance according to the value(s) in the table below.

HINT:

This inspection is to check the LIN communication line in the instrument panel junction block assembly that connects the wire harness to the built-in main body ECU (multiplex network body ECU).

Standard Resistance:

Tester Connection

Condition

Specified Condition

2B-17 - MB-16 (LIN2)

Always

Below 1 Ω
NG

REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

OK

2.

CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY - ROOF SUNSHADE ECU (SLIDING ROOF DRIVE GEAR ASSEMBLY))

(a) Disconnect the w1 roof sunshade ECU (sliding roof drive gear assembly) connector.

(b) Measure the resistance according to the value(s) in the table below.

NOTICE:

Make sure that each ECU is in sleep mode before performing the inspection. To enter sleep mode, turn the engine switch from ON to off and wait for 180 seconds or more without operating any switches.

Standard Resistance:

Tester Connection

Condition

Specified Condition

2B-17 -w1-7 (LIN)

Engine switch off

Below 1 Ω

w1-7 (LIN) or 2B-17 - Body ground

Engine switch off

10 kΩ or higher
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

3.

CHECK HARNESS AND CONNECTOR (ROOF SUNSHADE ECU (SLIDING ROOF DRIVE GEAR ASSEMBLY) - BATTERY, BODY GROUND)

(a) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection

Condition

Specified Condition

w1-1 (+B) - w1-2 (E)

Always

11 to 14 V

(b) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

w1-2 (E) - Body ground

Always

Below 1 Ω
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

4.

REPLACE ROOF SUNSHADE ECU (SLIDING ROOF DRIVE GEAR ASSEMBLY)

(a) Replace the roof sunshade ECU (sliding roof drive gear assembly).

Click here

NEXT

5.

CHECK FOR DTC

(a) Clear the DTCs.

Click here

Body Electrical > Main Body > Clear DTCs

(b) Recheck for DTCs.

Body Electrical > Main Body > Trouble Codes

OK:

DTC B2329 is not output.

OK

END (ROOF SUNSHADE ECU (SLIDING ROOF DRIVE GEAR ASSEMBLY) WAS DEFECTIVE)
NG

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

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