FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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P2103








3UZ-FE ENGINE CONTROL SYSTEM: SFI SYSTEM: P2102: Throttle Actuator Control Motor Circuit Low

DTC P2102 - Throttle Actuator Control Motor Circuit Low

DTC P2103 - Throttle Actuator Control Motor Circuit High

DESCRIPTION

The throttle actuator is operated by the ECM and it opens and closes the throttle valve.
The opening angle of the throttle valve is detected by the throttle position sensor which is mounted on the throttle body. The throttle position sensor provides feedback to the ECM. This feedback allows the ECM to control the throttle actuator and monitor the throttle opening angle as the ECM responds to driver inputs.
HINT: The Electronic Throttle Control System (ETCS) does not use a throttle cable.





MONITOR DESCRIPTION

The ECM monitors the flow of electrical current through the electronic throttle actuator, and detects malfunctions or open circuits in the throttle actuator based on the value of the electrical current. When the current deviates from the standard values, the ECM concludes that there is a fault in the throttle actuator. Or, if the throttle valve is not functioning properly (for example, stuck ON), the ECM concludes that there is a fault, illuminates the MIL and sets a DTC.
Example:
The ECM determines that the current has deviated from the standard values when one of the following is detected: 1) the current is more than 10 A, or 2) the actuator driving duty ratio exceeds 80% and the current is less than 0.5 A. Then the ECM turns on the MIL and a DTC is set.
This monitor runs after the engine is started, idled for 5 seconds and then quickly revved at a high rpm several times.

MONITOR STRATEGY





TYPICAL ENABLING CONDITIONS





P2102:





P2103:





TYPICAL MALFUNCTION THRESHOLDS

P2102:





P2103:





FAIL-SAFE

If the ETCS has a malfunction, the ECM cuts off current to the throttle actuator. The throttle valve returns to a predetermined opening angle (approximately 7°) by the force of 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 accelerator pedal opening angle to enable the vehicle to continue at a minimal speed.
If the accelerator pedal is depressed firmly and slowly, the vehicle can be driven slowly.
If a "pass" condition is detected and then the ignition switch is turned OFF, the fail-safe operation will stop and the system will return to normal.

WIRING DIAGRAM





INSPECTION PROCEDURE
HINT:
- Read freeze frame data using the Techstream. Freeze frame data records the engine conditions when a malfunction is detected. When troubleshooting, freeze frame data can help determine if the vehicle was running or stopped, 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.
- The throttle actuator current (Throttle Motor Current) and the throttle actuator duty ratio (Throttle Motor Open Duty / Throttle Motor Close Duty) can be read using the Techstream. However, the ECM shuts off the throttle actuator current when the ETCS malfunctions.

PROCEDURE

1. INSPECT THROTTLE BODY (THROTTLE ACTUATOR RESISTANCE)




(a) Disconnect the T26 actuator connector.
(b) Measure the resistance between terminals 1 and 2 of the throttle body.
Standard resistance:






NG -- REPLACE THROTTLE BODY
OK -- Continue to next step.
2. CHECK WIRE HARNESS (THROTTLE ACTUATOR - ECM)




(a) Disconnect the T26 actuator connector.
(b) Disconnect the E2 ECM connector.
(c) Measure the resistance of the wire harness side connectors.
Standard resistance:






NG -- REPAIR OR REPLACE HARNESS AND CONNECTOR
OK -- Continue to next step.
3. INSPECT THROTTLE BODY
(a) Check the throttle body for foreign objects.
OK:
No foreign objects between the throttle valve and the housing.
NG -- REMOVE FOREIGN OBJECT AND CLEAN THROTTLE BODY
OK -- Continue to next step.
4. INSPECT THROTTLE VALVE
(a) Check if the throttle valve can open and close smoothly.
OK:
Throttle valve can move smoothly.
NG -- REPLACE THROTTLE BODY
OK -- REPLACE ECM