P2127
FA20 ENGINE CONTROL: SFI SYSTEM: P2122, P2123, P2127, P2128, P2138; Throttle / Pedal Position Sensor / Switch "D" Circuit Low Input; 2013 MY FR-S [03/2012 -]
P2122 - Throttle / Pedal Position Sensor / Switch "D" Circuit Low Input
P2123 - Throttle / Pedal Position Sensor / Switch "D" Circuit High Input
P2127 - Throttle / Pedal Position Sensor / Switch "E" Circuit Low Input
P2128 - Throttle / Pedal Position Sensor / Switch "E" Circuit High Input
P2138 - Throttle / Pedal Position Sensor / Switch "D" / "E" Voltage Correlation
DESCRIPTION
HINT
* These DTCs relate to the accelerator pedal sensor assembly.
* This electronic throttle control system does not use a throttle cable.
The accelerator pedal sensor assembly is mounted on the accelerator pedal bracket and has 2 sensor circuits: VPA (main) and VPA2 (sub). This sensor is a non-contact type. It uses Hall-effect elements in order to yield accurate signals, even in extreme conditions. 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).
The ECM monitors the actual accelerator pedal operating angle (throttle valve opening angle) through the signals from VPA and VPA2, and controls the throttle actuator according to these signals.
HINT
The accelerator pedal position output voltages of VPA and VPA2 are almost the same.
MONITOR DESCRIPTION
The accelerator pedal position sensor is mounted on the accelerator pedal bracket. The accelerator pedal position sensor has 2 sensor elements and 2 signal outputs: VPA and VPA2. VPA is used to detect the actual accelerator pedal angle (used for engine control) and VPA2 is used to detect malfunctions in VPA. When the difference between the output voltages of VPA and VPA2 deviates from the standard, the ECM determines that the accelerator pedal position sensor is malfunctioning. The ECM turns on the MIL and stores the DTC.
MONITOR STRATEGY
TYPICAL ENABLING CONDITIONS
P2122, P2123, P2127, P2128
P2138
TYPICAL MALFUNCTION THRESHOLDS
P2122
P2123
P2127
P2128
P2138
COMPONENT OPERATING RANGE
CONFIRMATION DRIVING PATTERN
1. Connect the Techstream to the DLC3.
2. Turn the ignition switch to ON and turn the Techstream on.
3. Clear DTCs (even if no DTCs are stored, perform the clear DTC operation) Reading and Clearing Diagnostic Trouble Codes.
4. Turn the ignition switch off and wait for at least 30 seconds.
5. Turn the ignition switch to ON and turn the Techstream on.
6. Start the engine and warm it up until the engine coolant temperature reaches 75°C (167°F) or higher.
7. Depress the accelerator pedal fully and release the accelerator pedal.
8. Drive the vehicle at 10 km/h (6.25 mph) or more for 1 minute or more [A].
CAUTION:
When performing the confirmation driving pattern, obey all speed limits and traffic laws.
9. Enter the following menus: Powertrain / Engine / Trouble Codes.
10. Read pending DTCs.
HINT
* If a pending DTC is output, the system is malfunctioning.
* If a pending DTC is not output, perform the following procedure.
11. Enter the following menus: Powertrain / Engine / Utility / All Readiness.
12. Input the DTC: P2122, P2123, P2127, P2128 or P2138.
13. Check the DTC judgment result.
HINT
* If the judgment result shows NORMAL, the system is normal.
* If the judgment result shows ABNORMAL, the system has a malfunction.
14. If the test result is INCOMPLETE or N/A and no DTC is output, perform a universal trip and check for permanent DTCs Reading and Clearing Diagnostic Trouble Codes.
HINT
* If a permanent DTC is output, the system is malfunctioning.
* If no permanent DTC is output, the system is normal.
FAIL-SAFE
The accelerator pedal position sensor has 2 (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 2 sensor circuits and switches to fail-safe mode. In fail-safe 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 normal.
WIRING DIAGRAM
INSPECTION PROCEDURE
HINT
* This DTC relates to the accelerator pedal position sensor.
* Read freeze frame data using the Techstream. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. 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 VALUE USING TECHSTREAM (ACCELERATOR PEDAL POSITION SENSOR)
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to ON.
(c) Turn the Techstream on.
(d) Enter the following menus: Powertrain / Engine / Data List / Accel Sensor Out No. 1 and Accel Sensor Out No. 2.
(e) Read the values displayed on the Techstream.
Standard Voltage:
Result
B -- CHECK FOR INTERMITTENT PROBLEMS Check For Intermittent Problems
A -- Continue to next step.
2. CHECK HARNESS AND CONNECTOR (ECM - ACCELERATOR PEDAL SENSOR)
(a) Disconnect the ECM connector.
(b) Disconnect the accelerator pedal sensor connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance (Check for open):
Standard Resistance (Check for short):
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
3. INSPECT ECM (VC VOLTAGE)
(a) Disconnect the accelerator pedal sensor connector.
(b) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
NG -- REPLACE ECM Removal
OK -- Continue to next step.
4. REPLACE ACCELERATOR PEDAL SENSOR ASSEMBLY
(a) Replace the accelerator pedal sensor assembly Removal.
NEXT -- Continue to next step.
5. CHECK WHETHER DTC OUTPUT RECURS (DTC P2122, P2123, P2127, P2128 OR P2138)
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to ON.
(c) Turn the Techstream on.
(d) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.
(e) Turn the ignition switch off and wait for at least 30 seconds.
(f) Turn the ignition switch to ON and turn the Techstream on.
(g) Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.
(h) Enter the following menus: Powertrain / Engine / Trouble Codes.
(i) Read DTCs.
Result
B -- REPLACE ECM Removal
A -- END