Guide To P2129 OBD Error Code Solutions

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Error code P2129? Seeing it again and again? Don’t worry, Parts Avatar has a solution! Here’s all you need to know about the error code P2129. This OBD-II code decreased engine performance is generally known as a throttle/pedal position sensor/switch "E" circuit intermittent. The role of controlling the throttle valve opening is played by the electronic throttle control system (ETCS). The accelerator pedal position sensor (APP) transmits a signal to the engine control module (PCM) telling the PCM how much power the driver is requesting from the engine when the driver presses the accelerator pedal. The throttle plate opens according to the commands of the PCM. The code P2129is stored, when the PCM notifies an improper opening of the throttle via a signal from the APP sensor. Also, the PCM at times puts the engine into the "limp home mode" thereby limiting the availability of power from the engine to stop the unwanted acceleration.

The powertrain control module (PCM) has the accelerator pedal position (APP) sensor as an input, that is used to determine the amount of torque requested by the operator. In total there are 2 pedal position signals that can be found in the sensor. It should be noted that, both the signals, APP and APP2, have a positive slope (increasing angle, increasing voltage), but are offset and increase at changing rates. These 2 pedal position signals ensure that the PCM gets a right input even if 1 signal has a problem. The PCM plays the role of ascertaining if a signal is incorrect by calculating where it should be implied from the other signals. If there is a problem present within one of the circuits, the other input is utilized. Located between the PCM and APP sensor assembly are 2 reference voltage circuits, 2 signal return circuits, and 2 signal circuits (a total of 6 circuits and pins). The pedal position signal is altered by the PCM into pedal travel degrees (rotary angle). There is a software that performs the task of converting these degrees to counts, which is the input to the torque-based strategy.

What causes this problem with the Throttle Position Sensor/Switch E Circuit Intermittent?

• A damaged or wrongly adjusted TPS
• The TPS "E" wiring or connectors open or short circuited
• A defective throttle plate
• A malfunctioning PCM or a PCM programming error

1. Accelerator pedal position assembly - Check engine light flashing? Alarmed? Not only this but a whole lot of problems including issues with the throttle body and throttle pressure are likely to follow a malfunction in the accelerator pedal position assembly. Mend or restore it now!
2. Throttle control motor - Trouble code P2129? Well, a lot of problems are likely to accompany a damaged throttle control motor including no acceleration, lack of power and a rough idle. Tune into Parts Avatar if you are planning to get your throttle control motor repaired or replaced.
3. Throttle position sensor - A lot of issues can arise due to a fault in the throttle position sensor. Another after effect of a faulty throttle position sensor is that you may observe that the car will accelerate, but not beyond a speed of 20 - 30 MPH. Also a decreased fuel economy is likely to be observed too. Repair or replace now!
4. Powertrain control module - The powertrain control module is the part that is often defined a the brain of the system. A badly functioning engine, constant halts while starting the engine (as it ensures the smooth functioning of the camshaft and crankshaft) and a consequent failure in the system is accompanied with a faulty powertrain control module.
5. Throttle position sensor connector - Having problems with the throttle position sensor connector? It should be noted that a disconnected or shorted throttle position sensor connector leads to deteriorating the overall functionality of the throttle position sensor. Looking for a new one? Don’t you worry, Parts Avatar has it all. Repair or replace it now in order to get rid of these problems caused by the error code P2129.
6. Pedal position sensor - Weary and damaged pedal position sensor can often be problematic. So to add some spark to your ride you definitely need the perfect quality pedal position sensor offered at Parts Avatar. Isn’t that just the perfect deal?

Willing to know the symptoms to OBD code P2129? If yes, then you have arrived at the right place. We at Parts Avatar have listed out few common symptoms associated with throttle position sensor/switch E circuit intermittent.

Common Symptoms

• Hesitancy in acceleration
• Black smoke emitting from engine exhaust (particularly on start up)
• A slow engine start-up (especially on cold start)
• A falling fuel efficiency

Have a look at some ways with which you can correct the P2129 code:

• Repair or replace a damaged or wrongly adjusted TPS as soon as possible
• Replacements or repairs should be performed of all the open or shorted wiring and connectors in the TPS "E"
• Mend or restore a defective PCM. Sometimes it is essential to perform a reprogramming or update
• A broken or unsound throttle plate should be replaced or repaired

There is no need to get strained if your OBD code is still flashing up as we are here at your service. Have a look at our superior variety of accelerator pedal position assembly, throttle control motor, throttle position sensor, powertrain control module, throttle position sensor connector, pedal position sensor and many more. Now all your problems would vanish within no time.

Here are some steps which you should follow in order to diagnose this P2129 fault code:

• Firstly it is always good to check the technical service bulletins (TSB) for the vehicle. Also, with a manufacturer, diagnosing becomes easy (with a known fix) that helps save both time and money
• Use a diagnostic scanner, a digital volt/ohmmeter (DVOM), and an accurate vehicle information source (ALL DATA DIY) to probe the code P2129
• It is essential to begin with a visual inspection of all system related wiring and connectors. The throttle plate should also be tested for signs of carbon coking or any damage. Repairs or replacements should be performed of all the damaged wiring or components. Then the throttle body and TPS should also be rechecked
• The scanner should be connected to the diagnostic connector. All the stored trouble codes should be restored and written down for future reference. Any related freeze frame data should be recorded too (as it proves to be helpful if the code is intermittent). Next, the codes should be cleared and the vehicle should be test driven. Carry on with the diagnosis if the code reappears. If the code fails to return, the condition should be left to worsen before a correct diagnosis can be made. The vehicle should be operated normally until the PCM goes into the readiness mode or the code returns.
• Next, we advise you to check for technical service bulletins (TSB) that are valid to the particular error (and vehicle) by referring to the vehicle information source. The information contained (if valid) should be used in the appropriate TSB to help with the diagnosis. It should be noted that these TSBs can be extremely helpful while diagnosing an intermittent condition.
• Also, the scanner data stream may produce important information related to misfiring and inconsistencies in the throttle position sensor. Well, if the scanner data stream is narrowed down to display only pertinent data, you might get a more precise data response. Utilize the DVOM to test the TPS, if no signs of misfiring are identified. By making use of the DVOM, you’ll get an access to live data if the correct test leads are connected to the ground and signal circuits. It is advised that you should watch the DVOM display while the throttle is operated manually.
• Next, the voltage should be checked for any signs of misfiring as the throttle activates slowly from the closed position to wide open throttle. The voltage can be seen typically ranging from 0.5-volts at closed throttle to 4.5-volts at wide open throttle. If in case, you come across a misfiring condition or other inconsistencies are detected, a wrongly adjusted or damaged sensor should be suspected

Common mistakes when diagnosing the P2129 code

Here we have listed a few common mistakes that should be avoided while diagnosing the error code P2129:

Often, the symptoms and stored codes present (as a reaction to a communication failure) are misdiagnosed and repaired as the basis of the problem. This leads to a failed diagnosis, further inviting problems like engine glitches, lean exhaust codes, fuel injector codes and a whole lot of drivability issues or a transmission code. A controller communication code is likely to follow too (adding to the difficulties leading to a misdiagnose). It is advised to diagnose and treat the stored codes in the order in which they were stored. As this not only simplifies the problems but also increases the chances of an accurate diagnosis. The freeze frame data should be used verify the order of the codes while the procedure is being performed.