P2129 OBD-II: Throttle/Pedal Position Sensor/Switch "E" Circuit Intermittent
P2129 Severity
Should you fix P2129 yourself?
Identifying an OBD code is just the start of a complete diagnostic routine. Most trouble codes are caused by a sensor reporting a value that is out of range. Just replacing a sensor may not fix underlying issues. Be sure to understand the code, the part or system in your car that the code refers to, and the risks of delaying professional repair.
Proper diagnosis will save you time and money on unnecessary repairs.
Urgent codes indicate immediate action is necessary. These are urgent and significant malfunctions that can cause severe damage to the vehicle or harm the driver and passengers.
What causes OBD-II fault code P2129?
The electronic throttle control system (ETCS) controls the throttle valve opening. When the driver presses the accelerator pedal, the Accelerator Pedal Position Sensor (APP) sends a signal to the engine's control module (PCM) telling the PCM how much power the driver is requesting from the engine. The PCM then commands the throttle plate to open accordingly. If the PCM detects the Electronic Throttle Control is not operating as requested, the PCM will set code P2129. The PCM may also put the engine into "limp home mode", limiting the available power from the engine to prevent unwanted acceleration.
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OBD II Fault Code
- OBD II P2129
OBD-II Code Decreased engine performance is defined as a Throttle/Pedal Position Sensor/Switch "E" Circuit Intermittent
The electronic throttle control system (ETCS) controls the throttle valve opening. When the driver presses the accelerator pedal, the Accelerator Pedal Position Sensor (APP) sends a signal to the engine's control module (PCM) telling the PCM how much power the driver is requesting from the engine. The PCM then commands the throttle plate to open accordingly. If the PCM detects the Electronic Throttle Control is not operating as requested, the PCM will set code P2129. The PCM may also put the engine into "limp home mode", limiting the available power from the engine to prevent unwanted acceleration.
Decreased engine performance Symptoms
- Decreased engine performance
- Engine may enter limp home mode (reduced performance)
Common Problems That Trigger the P2129 Code
- Accelerator Pedal Position (APP) assembly failure
- Powertrain Control Module (PCM) failure
- Throttle control motor failure
- Wiring issue
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