P2122

2TR-FE ENGINE CONTROL SYSTEM: SFI SYSTEM: P2120,P2122,P2123,P2125,P2127,P2128,P2138: Throttle / Pedal Position Sensor / Switch "D" Circuit


CAUTION / NOTICE / HINT

HINT
These DTCs relate to the Accelerator Pedal Position (APP) sensor.

DESCRIPTION

HINT
- This ETCS (Electronic Throttle Control System) does not use a throttle cable.
- The Accelerator Pedal Position (APP) sensor is mounted on the accelerator pedal bracket and has 2 sensor circuits: VPA (main) and VPA2 (sub). This sensor is a non-contact type, and uses Hall-effect elements, in order to yield accurate signals, even in extreme driving conditions, such as at high speeds as well as very low speeds. The voltage, which is applied to terminals VPA and VPA2 of the ECM, varies between 0 V and 5 V in proportion to the operating angle of the accelerator pedal (throttle valve). A signal from VPA indicates the actual accelerator pedal opening angle (throttle valve opening angle) and is used for engine control. A signal from VPA2 conveys the status of the VPA circuit and is used to check the APP sensor itself.
- The ECM monitors the actual accelerator pedal opening angle (throttle valve opening angle) through the signals from VPA and VPA2, and controls the throttle actuator according to these signals.









HINT
When any of these DTCs are set, check the APP sensor voltage by entering the following menus: Powertrain / Engine and ECT / Data List / ETCS / Accelerator Position No. 1 and Accelerator Position No. 2.





HINT
- Accelerator pedal positions are expressed as voltages.
- AP stands for Accelerator Pedal.

MONITOR DESCRIPTION

When either of the voltage outputs of VPA or VPA2 deviates from the standard range, or the difference between the voltage outputs of the 2 sensor circuits is less than the threshold, the ECM determines that there is a malfunction in the APP sensor. The ECM then illuminates the MIL and sets a DTC.

Example:

When the voltage output of VPA drops below 0.4 V for more than 0.5 seconds when the accelerator pedal is fully depressed, DTC P2122 is set.

If the malfunction is not repaired successfully, a DTC is set 2 seconds after the engine is next started.

MONITOR STRATEGY





TYPICAL ENABLING CONDITIONS





TYPICAL MALFUNCTION THRESHOLDS

P2120:





P2122:





P2123:





P2125:





P2127:





P2128:





P2138:





COMPONENT OPERATING RANGE





FAIL-SAFE

When any of DTCs P2120, P2121, P2122, P2123, P2125, P2127, P2128 and P2138 are set, the ECM enters fail-safe mode. If either of the 2 sensor circuit malfunctions, the ECM uses the remaining circuit to calculate the accelerator pedal position to allow the vehicle to continue driving. If both of the circuits malfunction, the ECM regards the accelerator pedal as being released. As a result, the throttle valve is closed and the engine idles.

Fail-safe mode continues until a pass condition is detected, and the ignition switch is turned to OFF.

WIRING DIAGRAM





INSPECTION PROCEDURE

HINT
Read freeze frame data using the Techstream. Freeze frame data records the engine condition when malfunctions are detected. 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

1. READ DATA LIST (ACCELERATOR POSITION NO. 1 AND ACCELERATOR POSITION NO. 2)





(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON and turn the Techstream ON.

(c) Enter the following menus: Powertrain / Engine and ECT / Data List / ETCS / Accelerator Position No. 1 and Accelerator Position No. 2.

(d) Read the values displayed on the Techstream.

Standard Voltage:





OK -- CHECK WHETHER DTC OUTPUT RECURS (ACCELERATOR PEDAL POSITION SENSOR DTCS)
NG -- Continue to next step.

2. CHECK HARNESS AND CONNECTOR (ACCELERATOR PEDAL POSITION SENSOR - ECM)





(a) Disconnect the A19 Accelerator Pedal Position (APP) sensor connector.

(b) Disconnect the E8 ECM connector.

(c) Check the resistance.

Standard Resistance (Check for open):





Standard Resistance (Check for short):





(d) Reconnect the APP sensor connector.

(e) Reconnect the ECM connector.

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

3. INSPECT ECM (VCPA AND VCP2 VOLTAGE)





(a) Disconnect the APP sensor connector.

(b) Turn the ignition switch to ON.

(c) Measure the voltage between the terminals of the ECM connector.

Standard Voltage:





(d) Reconnect the APP sensor connector.

NG -- REPLACE ECM Removal
OK -- Continue to next step.

4. REPLACE ACCELERATOR PEDAL ROD ASSEMBLY

(a) Replace the accelerator pedal rod assembly Removal.

NEXT -- Continue to next step.

5. CHECK WHETHER DTC OUTPUT RECURS (ACCELERATOR PEDAL POSITION SENSOR DTCS)

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON and turn the Techstream ON.

(c) Clear DTCs DTC Check / Clear.

(d) Allow the engine to idle for 15 seconds.

(e) Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

(f) Read DTCs.

Result:





B -- END

A -- REPLACE ECM Removal