Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual: How To Proceed With Troubleshooting

Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual / Vehicle Exterior / Sliding Roof / Convertible / Panoramic Moon Roof System / How To Proceed With Troubleshooting

CAUTION / NOTICE / HINT

HINT:

  • Use the following procedure to troubleshoot the panoramic moon roof system.
  • *: Use the Techstream.

PROCEDURE

1.

VEHICLE BROUGHT TO WORKSHOP
NEXT

2.

CUSTOMER PROBLEM ANALYSIS

HINT:

  • In troubleshooting, confirm that the problem symptoms have been accurately identified. Preconceptions should be discarded in order to make an accurate judgment. To clearly understand what the problem symptoms are, it is extremely important to ask the customer about the problem and the conditions at the time the malfunction occurred.
  • Gather as much information as possible for reference. Past problems that seem unrelated may also help in some cases.
  • The following 5 items are important points for problem analysis:

    What

    Vehicle model, system name

    When

    Date, time, occurrence frequency

    Where

    Road conditions

    Under what conditions?

    Driving conditions, weather conditions

    How did it happen?

    Problem symptoms
NEXT

3.

PRE-CHECK

(a) Measure the battery voltage.

Standard Voltage:

11 to 14 V

If the voltage is below 11 V, recharge or replace the battery before proceeding to the next step.

(b) Check the fuses and relays.

(c) Check the connector connections and terminals to make sure that there are no abnormalities such as loose connections, deformation, etc.

NEXT

4.

CHECK COMMUNICATION FUNCTION OF CAN COMMUNICATION SYSTEM*

(a) Using the Techstream, check for CAN communication system DTCs.

Click here

Result

Proceed to

CAN DTCs are not output

A

CAN DTCs are output

B
B

GO TO CAN COMMUNICATION SYSTEM

A

5.

CHECK COMMUNICATION FUNCTION OF LIN COMMUNICATION SYSTEM*

(a) Using the Techstream, check for LIN communication system DTCs.

Click here

Result

Proceed to

LIN DTCs are not output

A

LIN DTCs are output

B
B

GO TO LIN COMMUNICATION SYSTEM

A

6.

CHECK FOR DTC*

(a) Check for DTCs and make a note of any codes that are output.

Click here

Body Electrical > Sliding Roof > Trouble Codes Body Electrical > Sliding Sunshade > Trouble Codes

(b) Clear the DTCs.

Body Electrical > Sliding Roof > Clear DTCs Body Electrical > Sliding Sunshade > Clear DTCs

(c) Recheck for DTCs.

Body Electrical > Sliding Roof > Trouble Codes Body Electrical > Sliding Sunshade > Trouble Codes

Result

Proceed to

DTCs are not output

A

DTCs are output

B
B

GO TO DIAGNOSTIC TROUBLE CODE CHART

A

7.

PROBLEM SYMPTOMS TABLE

(a) Refer to Problem Symptoms Table.

Click here

Result

Proceed to

Fault is not listed in Problem Symptoms Table

A

Fault is listed in Problem Symptoms Table

B
B

GO TO STEP 9

A

8.

OVERALL ANALYSIS AND TROUBLESHOOTING*

(a) Operation Check

Click here

(b) Terminals of ECU

Click here

(c) Data List / Active Test

Click here

(d) Inspection

Click here

NEXT

9.

ADJUST, REPAIR OR REPLACE

(a) Check if the sliding roof ECU (sliding roof drive gear assembly) or roof sunshade ECU (sliding roof drive gear assembly) has been replaced, or the sliding roof glass sub-assembly, sliding roof housing panel, slide roof rail sub-assembly or sunshade trim sub-assembly has been adjusted, or removed and installed.

Result

Proceed to

The sliding roof ECU (sliding roof drive gear assembly) or roof sunshade ECU (sliding roof drive gear assembly) has been replaced, or the sliding roof glass sub-assembly, sliding roof housing panel, slide roof rail sub-assembly or sunshade trim sub-assembly has been adjusted, or removed and installed

A

The sliding roof ECU (sliding roof drive gear assembly) and roof sunshade ECU (sliding roof drive gear assembly) have not been replaced, and the sliding roof glass sub-assembly, sliding roof housing panel, slide roof rail sub-assembly and sunshade trim sub-assembly have not been adjusted, or removed and installed

B
B

GO TO STEP 11

A

10.

INITIALIZE PANORAMIC MOON ROOF SYSTEM

(a) Initialize the sliding roof ECU (sliding roof drive gear assembly).

Click here

(b) Initialize the roof sunshade ECU (sliding roof drive gear assembly).

Click here

NEXT

11.

CONFIRMATION TEST
NEXT

END
    System Description
    SYSTEM DESCRIPTION PANORAMIC MOON ROOF SYSTEM DESCRIPTION (a) The panoramic moon roof system controls the sliding roof operation using the sliding roof ECU (sliding roof drive gear assembly) and roof ...

    Operation Check
    OPERATION CHECK CHECK AUTO OPERATION FUNCTION (FOR SLIDING ROOF) NOTICE: Make sure that initialization has been completed before performing this inspection. Click here The sliding roof auto ope ...

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