Lexus RX (RX 350L, RX450h) 2016-2024 Repair Manual: Idle Control System (P050500)

• The difference between the target engine idle speed and actual engine idle speed exceeds the threshold and the idle control correction value is stuck at the upper or lower limit for 5 seconds or more.
• After driving at a vehicle speed of 10 km/h (6.25 mph) or more, the difference between the target and actual engine idle speed exceeds the threshold 5 times or more during a driving cycle, and then the system determines that the idle control correction value is stuck at the upper or lower limit, or that the idle control correction value has been changed by an amount that exceeds the threshold.

HINT:

• After repair has been completed, clear the DTC and then check that the vehicle has returned to normal by performing the following All Readiness check procedure.

  Click here

• When clearing the permanent DTCs, refer to the "CLEAR PERMANENT DTC" procedure.

  Click here

1. Connect the Techstream to the DLC3.
2. Turn the engine switch on (IG).
3. Turn the Techstream on.
4. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
5. Turn the engine switch off and wait for at least 30 seconds.
6. Turn the engine switch on (IG) [A].
7. Turn the Techstream on.
8. Start the engine and warm it up until the engine coolant temperature is 75°C (167°F) or higher with all the accessories switched off [B].
9. Idle the engine for 5 minutes or more [C].

   HINT:

   In order to keep the idling stable, turn off the A/C and all other electric loads and do not perform any shift operations.

10. Enter the following menus: Powertrain / Engine / Trouble Codes [D].
11. Read the pending DTCs.

    HINT:

    • If a pending DTC is output, the system is malfunctioning.
    • If a pending DTC is not output, perform the following procedure.
12. Enter the following menus: Powertrain / Engine / Utility / All Readiness.
13. Input the DTC: P050500.
14. Check the DTC judgment result.

    Techstream Display	Description
    NORMAL	DTC judgment completed System normal
    ABNORMAL	DTC judgment completed System abnormal
    INCOMPLETE	DTC judgment not completed Perform driving pattern after confirming DTC enabling conditions

    HINT:

    • If the judgment result is NORMAL, the system is normal.
    • If the judgment result is ABNORMAL, the system is malfunctioning.
    • If the judgment result is INCOMPLETE, perform steps [E] through [F].
    • [A] to [D]: Normal judgment procedure.

      The normal judgment procedure is used to complete DTC judgment and also used when clearing permanent DTCs.

    • When clearing the permanent DTCs, do not disconnect the cable from the battery terminal or attempt to clear the DTCs during this procedure, as doing so will clear the universal trip and normal judgment histories.
15. Accelerate the vehicle to 10 km/h (6.25 mph) or more, and then idle the engine for 20 seconds or more [E].

    CAUTION:

    When performing the confirmation driving pattern, obey all speed limits and traffic laws.

16. Repeat step [E] 5 times.
17. Enter the following menus: Powertrain / Engine / Trouble Codes [F].
18. Read the pending DTCs.

    HINT:

    • If a pending DTC is output, the system is malfunctioning.
    • If a pending DTC is not output, perform the following procedure.
19. Enter the following menus: Powertrain / Engine / Utility / All Readiness.
20. Input the DTC: P050500.
21. Check the DTC judgment result.

    Techstream Display	Description
    NORMAL	DTC judgment completed System normal
    ABNORMAL	DTC judgment completed System abnormal
    INCOMPLETE	DTC judgment not completed Perform driving pattern after confirming DTC enabling conditions

    HINT:

    • If the judgment result is NORMAL, the system is normal.
    • If the judgment result is ABNORMAL, the system is malfunctioning.
    • [A] to [F]: Normal judgment procedure.

      The normal judgment procedure is used to complete DTC judgment and also used when clearing permanent DTCs.

    • When clearing the permanent DTCs, do not disconnect the cable from the battery terminal or attempt to clear the DTCs during this procedure, as doing so will clear the universal trip and normal judgment histories.

HINT:

• The following conditions may also cause DTC P050500 to be stored:
  1. The floor carpet overlapping slightly onto the accelerator pedal, causing the accelerator pedal to be slightly depressed and therefore the throttle valve position to be slightly open.
  2. The accelerator pedal being not fully released.
• Refer to "Data List / Active Test" [Engine Speed, ISC F/B Torque and ISC F/B Learn Torque].

  Click here

• Read freeze frame data using the Techstream. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air fuel ratio was lean or rich, and other data from the time the malfunction occurred.

Vehicle Speed Sensor "A" No Signal (P050031)

DESCRIPTION Vehicles, which are equipped with ABS (Anti-lock Brake System), detect the vehicle speed using the skid control ECU (brake actuator assembly) and speed sensor. The speed sensor monitors th ...

Cold Start Idle Control System Performance (P050A00)

MONITOR DESCRIPTION This monitor will run when the engine is started at an engine coolant temperature of -10 to 50°C (14 to 122°F). The DTC will be stored after the engine idles for 13 seconds (2 tr ...

Other materials:

Lexus RX (RX 350L, RX450h) 2016-2024 Repair Manual > Occupant Classification System: Data List / Active Test
DATA LIST / ACTIVE TEST DATA LIST HINT: Using the Techstream to read the Data List allows the values or states of switches, sensors, actuators and other items to be read without removing any parts. This non-intrusive inspection can be very useful because intermittent conditions or signals may be dis ...

Lexus RX (RX 350L, RX450h) 2016-2024 Repair Manual > Rear Seat Side Airbag Assembly (w/ Rear No. 2 Seat): Removal
REMOVAL CAUTION / NOTICE / HINT The necessary procedures (adjustment, calibration, initialization, or registration) that must be performed after parts are removed, installed, or replaced during the rear seat airbag assembly removal/installation are shown below. Necessary Procedure After Parts Remove ...