Failsafe

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 circuits 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 OFF.

WIRING DIAGRAM

Accelerator Pedal Position Sensor

VPA EPA VCPA?

VPA2 EPA2 VCP2

LG-B

GR-B

LG-B

GR-B

26 19 21 27

VPA2

26 19 21 27

VPA2

EPA2 VCP2

HINT:

Read freeze frame data using an intelligent tester. Freeze frame data record 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.

READ VALUE OF INTELLIGENT TESTER (ACCEL POS #1 AND ACCEL POS #2)

Connect an intelligent tester to the DLC3.

Turn the ignition switch ON and turn the tester ON.

Select the following menu items: DIAGNOSIS /

and ACCEL POS #2.

Read the value displayed on the tester.

Standard Voltage

Accelerator Pedal Operations

ACCEL POS #1 (AP#1)

ACCEL POS #2 (AP#2)

Released

0.5 to 1.1 V

1.2 to 2.0 V

Depressed

2.6 to 4.5 V

3.4 to 5.0 V

Go to step 5

Go to step 5

CHECK HARNESS AND CONNECTOR (ACCELERATOR PEDAL POSITION SENSOR ECM)

Wire Harness Side:

VPA2 VCPA

VCP2

VCP2

Accelerator Pedal Position Sensor Connector

EPA VPA2 \VPA

ECM Connector

EPA2-^SJj

VCPA

Do It Yourself Car Diagnosis

Do It Yourself Car Diagnosis

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