P0122
DTC P0122 Throttle/Pedal Position Sensor/Switch "A" Circuit Low InputHINT: These DTCs relate to the throttle position sensor (w/o ETCS).
CIRCUIT DESCRIPTION
DTC Detecting Condition:
The throttle position sensor is mounted on the throttle body and detects the throttle valve opening angle. When the throttle valve is fully closed, a voltage of approximately 0.3 to 0.8 V is applied to terminal VTA of the ECM. The voltage applied to the terminal VTA of the ECM increases in proportion to the opening angle of the throttle valve and becomes approximately 3.2 to 4.9 V when the throttle valve is fully open. The ECM judges the vehicle driving conditions from this signal input from terminal VTA, and uses this information in calculations such as air-fuel ratio correction, power increase correction and fuel-cut control etc.
HINT: After confirming DTCs, confirm the throttle valve opening percentage and closed throttle position switch condition using the hand-held tester or the OBD II scan tool.
MONITOR DESCRIPTION
Monitor Strategy:
Typical Enabling Conditions:
Typical Malfunction Thresholds:
Component Operating Range:
The throttle position sensor varies its resistance with the angle of the throttle valve. The ECM applies a regulated reference voltage to the throttle position sensor positive terminal and calculates the angle of the throttle valve based on the current voltage at the throttle position sensor "signal" terminal.
When the throttle valve is near the fully closed position, the output voltage of the throttle position sensor is low. When it is near the fully open position, the output voltage is high.
If the ECM detects that the output voltage of the throttle position sensor is outside the normal range, the ECM interprets this as a malfunction in the throttle position sensor and sets a DTC.
Wiring Diagram:
INSPECTION PROCEDURE
Step 1 - 2:
Step 3:
Step 4 - 5:
HINT:
- If different DTCs related to different systems that have terminal E2 as the ground terminal are output simultaneously, terminal E2 may have an open circuit.
- Read freeze frame data using the hand-held tester or the OBD II scan tool. 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.
CHECK FOR INTERMITTENT PROBLEMS
HINT:
Hand-held tester only:
Inspect the vehicle's ECM using check mode. Intermittent problems are easier to detect with the hand-held tester when the ECM is in check mode. In check mode, the ECM uses 1trip detection logic, which is more sensitive to malfunctions than normal mode (default) that uses 2trip detection logic.
a. Clear DTCs.
b. Switch the ECM from normal mode to check mode using a hand-held tester.
c. Perform a simulation test.
d. Check and wiggle the harness(es), the connector(s) and terminal(s).