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 / Door / Hatch / Power Back Door System (w/ Outside Door Control Switch) / How To Proceed With Troubleshooting

CAUTION / NOTICE / HINT

HINT:

  • The power back door system troubleshooting procedure is based on the premise that the smart access system (for Entry Function) is operating normally. Check the power back door system first before troubleshooting the power back door system.

    Click here

  • Use the following procedure to troubleshoot the power back door 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 (MULTIPLEX NETWORK DOOR ECU)*

(a) Clear the DTCs.

Click here

Body Electrical > Back Door > Clear DTCs

(b) Recheck for DTCs.

Body Electrical > Back Door > 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) Terminals of ECU

Click here

(b) Data List / Active Test

Click here

(c) Operation Check

Click here

(d) Inspection

NEXT

9.

ADJUST, REPAIR OR REPLACE

(a) Check if the multiplex network door ECU has been removed and installed or replaced, or if any of the connectors have been disconnected, the cable has been disconnected from the negative (-) battery terminal with the back door open or if any of the fuses in the power source circuit have been removed and installed or replaced.

Result

Proceed to

The multiplex network door ECU has been removed and installed or replaced, or if any of the connectors have been disconnected, the cable has been disconnected from the negative (-) battery terminal with the back door open or if any of the fuses in the power source circuit have been removed and installed or replaced.

A

The multiplex network door ECU has not been removed and installed or replaced and none of the connectors have been disconnected, the cable has not been disconnected from the negative (-) battery terminal with the back door open and none of the fuses in the power source circuit have been removed and installed or replaced.

B
B

GO TO STEP 11

A

10.

INITIALIZE POWER BACK DOOR SYSTEM

(a) Initialize the power back door system.

Click here

NEXT

11.

CONFIRMATION TEST
NEXT

END
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