Lexus RX (RX 350L, RX450h) 2016-2024 Repair Manual: How To Proceed With Troubleshooting

CAUTION / NOTICE / HINT

PROCEDURE

1.	VEHICLE BROUGHT TO WORKSHOP

NEXT

2.	CUSTOMER PROBLEM ANALYSIS

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 FOR DTCs (HEALTH CHECK)

(a) Connect the Techstream to the DLC3.

(b) Turn the engine switch on (IG).

(c) Turn the Techstream on.

(d) Enter the following menus: System Select / Health Check.

(e) Check for DTCs.

(f) Turn the engine switch off.

Result	Proceed to
System DTCs other than DTCs related to the dynamic radar cruise control system (Radar Cruise 1) and dynamic radar cruise control system (Radar Cruise 2) are not output	A
System DTCs other than DTCs related to the dynamic radar cruise control system (Radar Cruise 1) and dynamic radar cruise control system (Radar Cruise 2) are output	B

B

GO TO DTC CHART

A

5.	CHECK MULTI-INFORMATION DISPLAY

(a) Check if a warning message is displayed on the multi-information display in the combination meter assembly.

HINT:

If more than one message is displayed, perform each inspection in the order of A, B and C.

Result	Proceed to
"Cruise Control Malfunction Visit Your Dealer" is displayed	A
One of the following warning messages is displayed: "Radar Cruise Control Unavailable See Owner's Manual" "Radar Cruise Control Unavailable"	B
No dynamic radar cruise control system warnings are displayed	C

B

GO TO STEP 9

C

GO TO STEP 11

A

6.	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

7.	CHECK FOR DTC*

(a) Using the Techstream, Check for DTCs.

Powertrain > Cruise Control > Trouble Codes Powertrain > Radar Cruise2 > Trouble Codes

Result	Proceed to
DTCs are not output	A
DTCs are output	B

A

GO TO STEP 9

B

8.	RECONFIRM DTC OUTPUT*

(a) Using the Techstream, Clear the DTCs.

Powertrain > Cruise Control > Clear DTCs Powertrain > Radar Cruise2 > 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) Recheck for DTCs.

Powertrain > Cruise Control > Trouble Codes Powertrain > Radar Cruise2 > Trouble Codes

Result	Proceed to
DTCs are not output	A
DTCs are output	B

A

GO TO SYMPTOM SIMULATION

B

GO TO DTC CHART

9.	CHECK VEHICLE CONTROL HISTORY*

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

Powertrain > Radar Cruise2 > 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) X2006, X2013, X2015, X2022, X2026 or X2028 is output	B
Vehicle Control History (RoB) other than X2006, X2013, X2015, X2022, X2026 or X2028 is output	C

A

GO TO SYMPTOM SIMULATION

B

GO TO VEHICLE CONTROL HISTORY

C

10.	RECONFIRM VEHICLE CONTROL HISTORY*

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

Powertrain > Radar Cruise2 > Utility

Tester Display
Vehicle Control History (RoB)

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

Powertrain > Radar Cruise2 > 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

11.	PROBLEM SYMPTOMS TABLE

HINT:

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 PROBLEM SYMPTOMS TABLE

A

12.	INSPECT MILLIMETER WAVE RADAR SENSOR ASSEMBLY (BEAM AXIS MISALIGNMENT READING)*

NOTICE:

Before checking for millimeter wave radar sensor beam axis misalignment, make sure that the radiator grille and front bumper are correctly installed and have not been damaged or modified.

(a) Adjust the reflector height.

Click here

(b) Place the reflector.

Click here

(c) Connect the Techstream to the DLC3.

(d) Turn the engine switch on (IG).

(e) Turn the Techstream on.

(f) Enter the following menus: Body Electrical / Front Radar Sensor / Utility / Front Beam Axis Misalignment Reading.

Body Electrical > Front Radar Sensor > Utility

Tester Display
Front Beam Axis Misalignment Reading

(g) Check the amount of misalignment.

Standard:

Vertical Direction	-5 to 5 deg.
Horizontal Direction	-0.6 to 0.6 deg.

HINT:

The millimeter wave radar sensor assembly automatically calibrates the beam axis while the vehicle is being driven. The specified values apply to the automatic calibration only and do not apply during manual beam axis calibration of the millimeter wave radar sensor assembly.

Result	Proceed to
The beam axis values are within specification	A
The beam axis values are not within specification	B

A

GO TO SYMPTOM SIMULATION

B

ADJUST MILLIMETER WAVE RADAR SENSOR ASSEMBLY