P2138
P2138 APP SensorComponent Description
The accelerator pedal position sensor is installed on the upper end of the accelerator pedal assembly. The sensor detects the accelerator position and sends a signal to the ECM.
Accelerator pedal position sensor has two sensors. These sensors are a kind of potentiometers which transform the accelerator pedal position into output voltage, and emit the voltage signal to the ECM. In addition, these sensors detect the opening and closing speed of the accelerator pedal and feed the voltage signals to the ECM. The ECM judges the current opening angle of the accelerator pedal from these signals and controls the throttle control motor based on these signals.
Idle position of the accelerator pedal is determined by the ECM receiving the signal from the accelerator pedal position sensor. The ECM uses this signal for the engine operation such as fuel cut.
On Board Diagnosis Logic
This self-diagnosis has the one trip detection logic.
NOTE: If DTC P2138 is displayed with DTC P0643, first perform the trouble diagnosis for DTC P0643. P0643
P2138:
FAIL-SAFE MODE
When the malfunction is detected, the ECM enters fail-safe mode and the MIL lights up.
Engine operating condition in fail-safe mode
The ECM controls the electric throttle control actuator in regulating the throttle opening in order for the idle position to be within +10 degrees.
The ECM regulates the opening speed of the throttle valve to be slower than the normal condition. So, the acceleration will be poor.
DTC Confirmation Procedure
NOTE: 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 8 V at idle.
WITH SDT
1. Start engine and let it idle for 1 second.
2. Check DTC.
3. If DTC is detected, go to [P2138 APP Sensor].
WITH GST
Follow the procedure "WITH SDT" above.
Diagnosis Procedure
Step 1:
Step 2:
Step 3-7:
Step 8-12:
Component Inspection
ACCELERATOR PEDAL POSITION SENSOR
1. Reconnect all harness connectors disconnected.
2. Turn ignition switch ON.
3. Check voltage between ECM terminals 106 (APP sensor 1 signal), 98 (APP sensor 2 signal) and ground under the following conditions.
4. If NG, replace accelerator pedal assembly and go to the next step.
5. Perform [Procedure After Replacing ECM]. Procedure After Replacing ECM
6. Perform [Procedure After Replacing ECM]. Procedure After Replacing ECM
7. Perform [Procedure After Replacing ECM]. Procedure After Replacing ECM