P0120
P0120 THROTTLE POSITION (TP) SENSOR
Component Description
Electric Throttle Control Actuator consists of throttle control motor, acceleration pedal position sensor, throttle position sensor, etc. The throttle position sensor responds to the throttle valve movement. The throttle position sensor has the two sensors. These sensors are a kind of potentiometers which transform the throttle valve position into output voltage, and emit the voltage signal to the ECM. In addition, these sensors detect the opening and closing speed of the throttle valve and feed the voltage signals to the ECM. The ECM judges the current opening angle of the throttle valve from these signals and the ECM controls the throttle control motor to make the throttle valve opening angle properly in response to driving condition.
Consult-II Reference Value In Data Monitor Mode:
On Board Diagnosis Logic
Malfunction is detected when
(Malfunction A) an excessively low or high voltage from the throttle position sensor 1 is sent to ECM,
(Malfunction B) an excessively low or high voltage from the throttle position sensor 2 is sent to ECM,
(Malfunction C) a difference between signals from sensor 1 and sensor 2 is out of the specified range,
(Malfunction D) ECM detects a voltage of power source for sensor is excessively low or high,
(Malfunction E) closed throttle position learning value is excessively low,
(Malfunction F) closed throttle position learning is not performed successfully, repeatedly,
(Malfunction G) throttle valve opening angle, computed by the ECM from the input signals of sensor 1 and sensor 2, is out of the normal range.
Fail-Safe Mode:
FAIL-SAFE MODE
ECM enters in fail-safe mode when the malfunction A, B, C,D or G is detected.
Possible Cause
MALFUNCTION A, B, C AND G
- Harness or connectors
(The throttle position sensor 1 or 2 circuit is open or shorted.)
- Electric throttle control actuator
MALFUNCTION D
- Harness or connectors
(The throttle position sensor 1, 2, accelerator pedal position sensor 1, 2, mass air flow sensor, power steering pressure sensor, refrigerant pressure sensor, absolute pressure sensor and EVAP system pressure sensor circuit is shorted.)
- ECM
(ECM pin terminal is bend or brake.)
MALFUNCTION E AND F
- Electric throttle control actuator
DTC Confirmation Procedure
NOTE:
- Perform "PROCEDURE FOR MALFUNCTION A, B, C, D AND G" first. If the 1st trip DTC cannot be confirmed, perform "PROCEDURE FOR MALFUNCTION E". If the 1st trip DTC cannot be confirmed, perform "PROCEDURE FOR MALFUNCTION F".
- If "DTC Confirmation Procedure" has been previously conducted, always turn ignition switch "OFF" and wait at least 10 seconds before conducting the next test.
TESTING CONDITION: Before performing the following procedure, confirm that battery voltage is more than 10 V at idle.
PROCEDURE FOR MALFUNCTION A, B, C, D AND G
With CONSULT-II
1. Turn ignition switch "ON".
2. Select "DATA MONITOR" mode with CONSULT-II.
3. Start engine and let it idle for 1 second.
4. If 1st trip DTC is detected, go to "MALFUNCTION A, B, C, D AND G" in "Diagnostic Procedure".
With GST
Follow the procedure "With CONSULT-II" above.
PROCEDURE FOR MALFUNCTION E
With CONSULT-II
1. Turn ignition switch "ON".
2. Select "DATA MONITOR" mode with CONSULT-II.
3. Turn ignition switch "OFF", wait at least 10 seconds.
4. Turn ignition switch "ON".
5. If 1st trip DTC is detected, go to "MALFUNCTION E AND F" in "Diagnostic Procedure".
With GST
Follow the procedure "With CONSULT-II" above.
PROCEDURE FOR MALFUNCTION F
With CONSULT-II
1. Turn ignition switch "ON".
2. Select "DATA MONITOR" mode with CONSULT-II.
3. Turn ignition switch "OFF", wait at least 10 seconds.
4. Turn ignition switch "ON".
5. Repeat steps 3 and 4, 32 times.
6. If 1st trip DTC is detected, go to "MALFUNCTION E AND F" in "Diagnostic Procedure".
With GST
Follow the procedure "With CONSULT-II" above.
EC-TPS-01:
Wiring Diagram
Diagnostic Procedure
Step 1:
Step 2 - 4:
Step 5 - 9:
Step 10:
MALFUNCTION A,B,C,D AND G
Step 1 - 2:
MALFUNCTION E AND F
Component Inspection
THROTTLE POSITION SENSOR
1. Reconnect all harness connectors disconnected.
2. Perform "Throttle Valve Closed Position Learning".
3. Turn ignition switch "ON".
4. Set selector lever to "D" position.
5. Check voltage between ECM terminals 98 (TP sensor 2), 108 (TP sensor 1) and engine ground under the following conditions.
6. If NG, replace electric throttle control actuator and go to the next step.
7. Perform "Throttle Valve Closed Position Learning"
8. Perform "Idle Air Volume Learning".Remove and Installation
ELECTRIC THROTTLE CONTROL ACTUATOR
Refer to "INTAKE MANIFOLD".