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

Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual / Engine & Hybrid System / Cruise Control / Lane Control System / How To Proceed With Troubleshooting

CAUTION / NOTICE / HINT

HINT:

  • Use the following procedure to troubleshoot the lane control 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 FOR DTCs*

(a) Using the Techstream, Check for DTCs.

Chassis > Lane Control > Trouble Codes

(b) Make a note of the output DTCs.

Result

Proceed to

DTCs are not output

A

DTCs are output

B
A

GO TO STEP 7

B

6.

RECONFIRM DTC OUTPUT*

(a) Using the Techstream, Clear the DTCs.

Chassis > Lane Control > Clear DTCs

(b) Reproduce the vehicle conditions that were present when the DTCs that were noted were stored.

HINT:

Refer to each corresponding DTC for details on the detection conditions.

Click here

(c) Using the Techstream, check for DTCs.

Chassis > Lane Control > Trouble Codes

Result

Proceed to

DTCs are not output

A

DTCs are output

B
B

GO TO DTC CHART

A

7.

CHECK VEHICLE CONTROL HISTORY*

(a) Using the Techstream, check for Vehicle Control History (RoB).

Chassis > Lane Control > Utility

Tester Display

Vehicle Control History (RoB)

(b) Make a note of the output Vehicle Control History (RoB).

Result

Proceed to

Vehicle Control History (RoB) is not output

A

Vehicle Control History (RoB) is output

B
A

GO TO SYMPTOM SIMULATION

B

8.

RECONFIRM VEHICLE CONTROL HISTORY*

(a) Using the Techstream, clear the Vehicle Control History (RoB).

Chassis > Lane Control > Utility

Tester Display

Vehicle Control History (RoB)

(b) Using the Techstream, check for Vehicle Control History (RoB).

Chassis > Lane Control > Utility

Tester Display

Vehicle Control History (RoB)

Result

Proceed to

Vehicle Control History (RoB) is not output

A

Vehicle Control History (RoB) is output

B
A

GO TO SYMPTOM SIMULATION

B

GO TO VEHICLE CONTROL HISTORY

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