Description
Hint:
Refer to dtc p2120 (see page es-282).
Monitor description
When the difference between the output voltages of vpa and vpa2 deviates from the standard, the ecm determines that the accelerator pedal position (app) sensor is malfunctioning. The ecm turns on the mil and the dtc is set.
Monitor strategy
Typical enabling conditions
Typical malfunction thresholds
Fail-safe
The app sensor has two (main and sub) sensor circuits. If a malfunction occurs in either of the sensor circuits, the ecm detects the abnormal signal voltage difference between the two sensor circuits and switches to limp mode. In limp mode, the functioning circuit is used to calculate the accelerator pedal opening angle to allow the vehicle to continue driving. If both circuits malfunction, the ecm regards the opening angle of the accelerator pedal as being fully closed. In this case, the throttle valve remains closed as if the engine is idling.
If a pass condition is detected and then the ignition switch is turned off, the fail-safe operation stops and the system returns to a normal condition.
Wiring diagram
Refer to dtc p2120 (see page es-286).
Inspection procedure
Hint:
Read freeze frame data using the intelligent tester. 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.
Hint:
If any dtcs other than p2121 are output, troubleshoot those dtcs first.
Standard voltage
System check
Hint:
Performing a system check enables the system,
which consists of multiple actuators, to be operated
without removing any parts. In addition, it can show
whether or not any dtcs are set, and can detect
potential malfunctions in the system. The system
check can be performed with the intelli ...
Components
...
Internal control module random access memory (ram) error
Description
The ecm continuously monitors its own internal memory status, internal
circuits, and output signals
transmitted to the throttle actuator. This self-check ensures that the ecm is
functioning properly. If any
malfunction is detected, the ecm sets the appropriate dtc and illumina ...