DTC 0403

NOTE: If both DTC P0120 (0403) and DTC P0510 (0203) are displayed, perform TROUBLE DIAGNOSIS FOR DTC P0510 first.






COMPONENT DESCRIPTION
The throttle position sensor responds to the accelerator pedal movement. This sensor is a kind of potentiometer which transforms the throttle position into output voltage, and emits the voltage signal to the ECM. In addition, the sensor detects the opening and closing speed of the throttle valve and feeds the voltage signal to the ECM.

Idle position of the throttle valve is determined by the ECM receiving the signal from the throttle position sensor. This one controls engine operation such as fuel cut.

On the other hand, the "Wide open and closed throttle position switch", which is built into the throttle position sensor unit, is not used for engine control.






CONSULT REFERENCE VALUE IN DATA MONITOR MODE
Specification data are reference values.






ECM TERMINALS AND REFERENCE VALUE
Specifications data are reference values, and are measured between each terminal and (25) (ECCS ground).






ON BOARD DIAGNOSIS LOGIC






FAIL-SAFE MODE
When the ECM enters the fail-safe mode, the MIL illuminates.

Perform "Procedure for malfunction A" first. If the DTC cannot be confirmed, perform "Procedure for malfunction B". If there is no problem on "Procedure for malfunction B", perform "Procedure for malfunction C".


DIAGNOSTIC TROUBLE CODE CONFIRMATION PROCEDURE


Procedure for malfunction A

NOTE: If "DIAGNOSTIC TROUBLE CODE CONFIRMATION PROCEDURE" has been previously conducted, always turn ignition switch "OFF" and wait at least 5 seconds before conducting the next test.

CAUTION: Always drive vehicle at a safe speed.

TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10 V at idle.

This test may be conducted with the drive wheels lifted in the shop or by driving the vehicle. If a road test is expected to be easier, it is unnecessary to lift the vehicle.


Without Scan Tools
(1) Start engine and maintain the following conditions for at least 5 consecutive seconds.

Vehicle speed: More than 4 km/h (2 MPH)

Selector lever: Suitable position except "P" or "N" position

(2) Turn ignition switch "OFF" and wait at least 5 seconds.
(3) Turn ignition switch "ON" and perform "Diagnostic Test Mode II (Self-diagnostic results)" with ECM.



Procedure for malfunction B

NOTE: If "DIAGNOSTIC TROUBLE CODE CONFIRMATION PROCEDURE" has been previously conducted, always turn ignition switch "OFF" and wait at least 5 seconds before conducting the next test.


Without Scan Tools
(1) Start engine and let it idle for at least 10 seconds.
(2) Turn ignition switch "OFF" and wait at least 5 seconds.
(3) Turn ignition switch "ON" and perform "Diagnostic Test Mode II (Self-diagnostic results)" with ECM.


Procedure for malfunction C

CAUTION: Always drive vehicle at a safe speed.

NOTE: If "DIAGNOSTIC TROUBLE CODE CONFIRMATION PROCEDURE" has been previously conducted, always turn ignition switch "OFF" and wait at least 5 seconds before conducting the next test.






Without Scan Tools
(1) Maintain the following conditions for at least 10 consecutive seconds.

Gear position: Suitable position
Engine speed: More than 2,000 rpm

Voltage between ECM terminal (54) and ground: More than 3 V
Voltage between ECM terminal (59) and ground: Less than 1.5 V

(2) Stop the vehicle, turn ignition switch "OFF", wait at least 5 seconds and then turn "ON".
(3) Perform "Diagnostic Test Mode II (Self-diagnostic results)" with ECM.






Electrical Diagrams






Circuit Connectors


DIAGNOSTIC PROCEDURE
If the trouble is duplicated after "Procedure for malfunction A", perform "Procedure A". If the trouble is duplicated after "Procedure for malfunction B", perform "Procedure A". If the trouble is duplicated after "Procedure for malfunction C", perform "Procedure B".






Procedure A






Procedure B



COMPONENT INSPECTION









Throttle position sensor
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch "OFF".
3. Disconnect throttle position sensor harness connector.
4. Make sure that resistance between terminals (2) and (3) changes when opening throttle valve manually.

If NG, replace throttle position sensor.

To adjust throttle position sensor, perform "BASIC INSPECTION".