Trouble code solution P2127: decoding, causes, resetting, meaning

Contents

Technical description and explained code P2127
Symptoms of vehicle malfunctions
Factors that can cause this error code
How to fix or reset OBD-2 code P2127
Diagnose and repair of problems
On which vehicles does this problem occur most frequently
Video

Fault code P2127 is called “Throttle/Pedal Position Sensor/Switch “E” Circuit Low Input” but in different programs it may be called differently. This fault designation applies to all vehicles equipped with OBD-II.

Technical description and explained code P2127

This Diagnostic Trouble Code (DTC) is a generic powertrain code. Error P2127 is considered a general code because it applies to all makes and models of vehicles. Although the specific repair steps may vary slightly depending on the model.

The throttle position sensor (TPS) reacts to the movement of the accelerator pedal. It is a type of potentiometer. It converts the throttle position into a voltage output and sends a voltage signal to the engine control module (ECM). It also determines the opening and closing speed of the throttle and provides a voltage signal to the ECM.

Code P2127 means that the vehicle’s computer has detected that the Throttle Position Sensor (TPS) “E” is reporting too low a voltage. On some vehicles, this lower limit is 0.17-0.20 volts (V).

Simply put, the throttle position sensor is used to determine which position the throttle is in. If the signal value is less than 0.17V, the PCM sets this code.

Symptoms of vehicle malfunctions

The main signal that an error P2127 has occurred is the Malfunction Indicator Lamp (MIL) is also known as the CheckEngine Light.

It can also be warning signs such as:

Check engine light on the control panel will illuminate.
Unstable or low idle speed.
Increased engine rpm at idle speed.
The engine stalls or fails to start.
The engine is not running evenly (pulsating).
No reaction on gas pedal.

Fault P2127 is quite serious, as its occurrence may cause problems with the engine RPM. To avoid dangerous situations on the road, if this code is detected, it is recommended to eliminate the fault as soon as possible.

Factors that can cause this error code

The error code P2127 can mean that one or more of the following problems have occurred:

Throttle position sensor circuit is open or bad electrical connection.
Throttle position sensor wiring harness is open or shorted to ground or other wire.
Throttle position sensor is defective.
Damaged computer (PCM).

How to fix or reset OBD-2 code P2127

Some suggested steps for troubleshooting and fix the error code P2127:

Read all stored data and error codes with an OBD-II scan tool. To find out when and under what circumstances error P2127 appeared.
Clear the error codes from the computer memory and test-drive the vehicle to find out if error P2127 appears again.
Visually inspect the electrical wiring and connections related to the throttle position “E” sensor for looseness and damage.
Compare readings of other throttle position sensors using a scan tool, replace faulty sensor if necessary.
Clear the error code from the computer memory again, and test drive the vehicle to see if the problem is resolved.

Diagnose and repair of problems

Carefully check the throttle position sensor (TPS), wiring connector, and wiring for breaks, etc. Repair or replace if necessary to clear error P2127.

Check the voltage at the TPS (refer to your vehicle’s service manual for more information). If the voltage is too low, this indicates a problem. Replace the sensor if necessary.

If recently replaced, you may need to adjust the TPS. On some vehicles, the installation instructions require a proper adjustment or adjustment (see your service manual for details).

If there are no symptoms, the problem may be intermittent, and clearing the code may temporarily resolve it. If this is the case, you should definitely check the wiring to make sure it is not rubbing or frayed anywhere, etc.