A25A-FXS (ENGINE CONTROL): SFI SYSTEM: P211900,P211904,P211977,P21199B; Throttle Actuator "A" Control Throttle Body Range/Performance; 2020 - 2022 MY Avalon HV [08/2019

The electronic throttle control system is composed of the throttle actuator, throttle position sensor, and ECM. The ECM operates the throttle actuator to regulate the throttle valve in response to a request from the hybrid system. The throttle position sensor detects the opening angle of the throttle valve, and provides the ECM with feedback so that the throttle valve can be appropriately controlled by the ECM.

MONITOR DESCRIPTION

The ECM determines the actual opening angle of the throttle valve from the throttle position sensor signal. The actual opening angle is compared to the target opening angle commanded by the ECM. If the difference between these two values is outside the standard range, the ECM interprets this as a malfunction in the electronic throttle control system, illuminates the MIL and stores this DTC.

MONITOR STRATEGY

TYPICAL ENABLING CONDITIONS

TYPICAL MALFUNCTION THRESHOLDS

CONFIRMATION DRIVING PATTERN

Connect the Techstream to the DLC3.
Turn the power switch on (IG).
Turn the Techstream on.
Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
Turn the power switch off and wait for at least 30 seconds.
Turn the power switch on (IG) [A].
Turn the Techstream on.
Put the engine in Inspection Mode (Maintenance Mode).
Click here
Start the engine.
Idle the engine for 20 seconds.
Enter the following menus: Powertrain / Engine / Trouble Codes [B].
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.
Enter the following menus: Powertrain / Engine / Utility / All Readiness.
Input the DTC: P211900, P211904, P211977 or P21199B.

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, fully depress and release the accelerator pedal 3 times, and then check the DTC judgment result [C].
[A] to [C]: 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 auxiliary battery terminal or attempt to clear the DTCs during this procedure, as doing so will clear the universal trip and normal judgment histories.

FAIL-SAFE

When this DTC is stored, the ECM enters fail-safe mode. During fail-safe mode, the ECM cuts the current to the throttle actuator, and the throttle valve is returned to a 7.5° throttle valve opening angle by the return spring. The ECM then adjusts the engine output, by controlling the fuel injection (intermittent fuel cut) and ignition timing, in accordance with the engine torque request signal sent from the hybrid vehicle control ECU assembly, to allow the vehicle to continue being driven at a minimal speed. If the accelerator pedal is depressed firmly and gently, the vehicle can be driven slowly.

Fail-safe mode continues until a pass condition is detected, and the power switch is then turned off.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

Vehicle Control History may be stored in the hybrid vehicle control ECU assembly if the engine is malfunctioning. Certain vehicle condition information is recorded when Vehicle Control History is stored. Reading the vehicle conditions recorded in both the Freeze Frame Data and Vehicle Control History can be useful for troubleshooting.
Click here

(Select Powertrain in Health Check and then check the time stamp data.)

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If any "Engine Malfunction" Vehicle Control History item has been stored in the hybrid vehicle control ECU assembly, make sure to clear it. However, as all Vehicle Control History items are cleared simultaneously, if any Vehicle Control History items other than "Engine Malfunction" are stored, make sure to perform any troubleshooting for them before clearing Vehicle Control History.
Click here

HINT:

Refer to "Data List / Active Test" [Throttle Position Sensor No.1 Voltage, Throttle Position Sensor No.2 Voltage, Throttle Position Command, Throttle Motor Current, Throttle Motor Duty Ratio (Open) and Throttle Motor Duty Ratio (Close)].
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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.

PROCEDURE

Powertrain > Engine > Trouble Codes

If any DTCs other than P211900, P211904, P211977 or P21199B are output, troubleshoot those DTCs first.

Powertrain > Engine > Clear DTCs

(d) Enter the following menus: Powertrain / Engine / Data List / Throttle Position Sensor No.1 Voltage and Throttle Position Command.

Powertrain > Engine > Data List

(e) Read the values displayed on the Techstream while fully depressing and releasing the accelerator pedal quickly.

During charge control, the engine speed is set at idle. Therefore, the engine speed will not increase when the accelerator pedal is depressed. In this case, perform this step after charge control has completed.

When a DTC is output, the system changes to fail-safe mode. Therefore, only use the data up until the time the DTC is stored for confirmation.

(a) Check for foreign matter between the throttle valve and housing. If necessary, clean the throttle body with motor assembly. Also, check that the throttle valve moves smoothly.

Perform "Inspection After Repair" after cleaning the throttle body with motor assembly.

Powertrain > Engine > Clear DTCs

(d) Enter the following menus: Powertrain / Engine / Data List / Throttle Position Sensor No.1 Voltage, Throttle Position Sensor No.2 Voltage and Throttle Position Command.

Powertrain > Engine > Data List

(e) Read the values displayed on the Techstream while wiggling the ECM wire harness.

Powertrain > Engine > Trouble Codes

(a) As the DTC was stored due to a change in the contact resistance of the connector, repair or replace the wire harness or connector.

Perform "Inspection After Repair" after replacing the throttle body with motor assembly.

Powertrain > Engine > Clear DTCs

(a) Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.