Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual: Sensor (Motor) Failure (B2341,B2344)

Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual / Vehicle Exterior / Sliding Roof / Convertible / Sliding Roof System / Sensor (Motor) Failure (B2341,B2344)

DESCRIPTION

When the sliding roof ECU (sliding roof drive gear sub-assembly) detects a motor malfunction and the sliding roof operation is stopped, DTC B2341 is stored.

When the sliding roof ECU (sliding roof drive gear sub-assembly) detects a gear position malfunction and the sliding roof operation is stopped, DTC B2344 is stored.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

B2341

Sensor (Motor) Failure

Sensor (motor) failure (The sliding roof ECU (sliding roof drive gear sub-assembly) enters fail-safe mode due to a problem with the motor)
  • Sliding roof ECU (Sliding roof drive gear sub-assembly)
  • Sliding roof switch (Map light assembly)
  • Wire harness or connector

B2344

Position Failure

Position failure (The sliding roof ECU (sliding roof drive gear sub-assembly) enters fail-safe mode due to a problem with the gear position)
  • Sliding roof ECU (Sliding roof drive gear sub-assembly)
  • Sliding roof switch (Map light assembly)
  • Wire harness or connector

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

  • If the sliding roof ECU (sliding roof drive gear sub-assembly) is removed and reinstalled or replaced, the sliding roof ECU (sliding roof drive gear sub-assembly) must be initialized.

    Click here

  • The sliding roof system uses the LIN communication system. First, confirm that there are no malfunctions in the LIN communication system. Refer to How to Proceed with Troubleshooting.

    Click here

PROCEDURE

1.

CHECK SLIDING ROOF OPERATION

(a) Check the sliding roof auto operation.

Click here

OK:

Auto operation operates normally.

NG

GO TO STEP 3

OK

2.

CHECK DTC OUTPUT

(a) Clear the DTCs.

Click here

Body Electrical > Sliding Roof > Clear DTCs

(b) Check for DTCs.

Body Electrical > Sliding Roof > Trouble Codes

OK:

DTCs B2341 and B2344 are not output.

OK

USE SIMULATION METHOD TO CHECK

NG

REPLACE SLIDING ROOF ECU (SLIDING ROOF DRIVE GEAR SUB-ASSEMBLY)

3.

INITIALIZE SLIDING ROOF ECU (SLIDING ROOF DRIVE GEAR SUB-ASSEMBLY)

(a) Check that the sliding roof ECU (sliding roof drive gear sub-assembly) can be initialized.

Click here

OK:

Sliding roof ECU (sliding roof drive gear sub-assembly) can be initialized.

NG

GO TO STEP 5

OK

4.

CHECK DTC OUTPUT

(a) Clear the DTCs.

Click here

Body Electrical > Sliding Roof > Clear DTCs

(b) Check for DTCs.

Body Electrical > Sliding Roof > Trouble Codes

OK:

DTCs B2341 and B2344 are not output.

OK

END (MALFUNCTION DUE TO INITIALIZATION FAILURE)
NG

REPLACE SLIDING ROOF ECU (SLIDING ROOF DRIVE GEAR SUB-ASSEMBLY)

5.

CHECK HARNESS AND CONNECTOR (SLIDING ROOF ECU (SLIDING ROOF DRIVE GEAR SUB-ASSEMBLY) - SLIDING ROOF SWITCH (MAP LIGHT ASSEMBLY) AND BODY GROUND)

(a) Disconnect the U11 sliding roof switch (map light assembly) connector.

(b) Disconnect the U2 sliding roof ECU (sliding roof drive gear sub-assembly) connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

U2-8 (CLS) - U11-12 (CLS)

Always

Below 1 Ω

U2-8 (CLS) or U11-12 (CLS) - Body ground

Always

10 kΩ or higher

U2-10 (OPN) - U11-11 (OPN)

Always

Below 1 Ω

U2-10 (OPN) or U11-11 (OPN) - Body ground

Always

10 kΩ or higher

U2-9 (CLS) - U11-24 (DOWN)

Always

Below 1 Ω

U2-9 (CLS) or U11-24 (DOWN) - Body ground

Always

10 kΩ or higher

U2-5 (OPN) - U11-23 (UP)

Always

Below 1 Ω

U2-5 (OPN) or U11-23 (UP) - Body ground

Always

10 kΩ or higher

U11-19 (GND) - Body ground

Always

Below 1 Ω

U2-2 (E) - Body ground

Always

Below 1 Ω
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

6.

INSPECT SLIDING ROOF SWITCH (MAP LIGHT ASSEMBLY)

(a) Remove the sliding roof switch (map light assembly).

Click here

(b) Inspect the sliding roof switch (map light assembly).

Click here

OK

REPLACE SLIDING ROOF ECU (SLIDING ROOF DRIVE GEAR SUB-ASSEMBLY)

NG

REPLACE SLIDING ROOF SWITCH (MAP LIGHT ASSEMBLY)

    Diagnostic Trouble Code Chart
    DIAGNOSTIC TROUBLE CODE CHART Sliding Roof System DTC No. Detection Item Link B2341 Sensor (Motor) Failure B2342 Switch Failure B2343 Position Initialization Incompl ...

    Switch Failure (B2342)
    DESCRIPTION This DTC is stored when the sliding roof ECU (sliding roof drive gear sub-assembly) detects that the sliding roof switch (map light assembly) is stuck for 30 seconds or more. DTC No. ...

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