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Just got those 2 DTC P0121 and P2138

wish someone can explain those 2 codes. Thanks.
 

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Just got those 2 DTC P0121 and P2138

wish someone can explain those 2 codes. Thanks.
For the P0121 Code....Throttle Position Sensor/Switch A Circuit Range/Performance Problem

What does that mean?...
The Throttle position sensor is a potentiometer that measures the amount of throttle opening. As the throttle is opened, the reading (measured in volts) goes up The powertrain control module (PCM) supplies a 5 Volt reference signal to the throttle position sensor (TPS) and usually a ground also. A general measurement is: at idle = .5 Volts; full throttle = 4.5 Volts. If the PCM detects that the throttle angle is greater or less than it should be for a specific RPM, it will set this code.

A Code P0121 May Mean that One or More of the following has Happened:
* TPS has intermittent open or short internally
* Harness is rubbing and causing an open or short in the wiring
* Bad connection at the TPS
* Bad PCM (less likely)
* Water or corrosion in connector or sensor


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For the Code P2138 Accelerator Pedal Position (APP) Sensor 1-2 Correlation
Typical accelerator pedal position sensor (APP)


What does that mean?....
If your vehicle has set a P2138 Accelerator Pedal Position (APP) Sensor 1-2 Correlation trouble code, read this description to find out what it means.

Many accelerator pedal position sensors actually have two sensors inside. The computer sends a 5-volt reference signal to both sensors and sees the return ground as a sign that the reference signal is reaching the sensors and returning back to the computer. A third wire carries that actual position signal.

Cause: On some vehicles, the IP to body harness connector, which carries the APP signal to the ECM/PCM, is located in the left hand kick panel area or inside the IP. Water intrusion into these areas could cause an electrical short in the APP circuits setting a P2138 code.

Correction Note: Make sure that no add-on/aftermarket equipment is electrically connected to the APP signals or to the other ECM/PCM five volt reference or return lines. These can generate false P2138 and/or other ETC System DTCs
 

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Just got those 2 DTC P0121 and P2138

wish someone can explain those 2 codes. Thanks.
P02138 is caused by a voltage difference between sensor 1 and sensor 2 of the APP The typical cause is water intrusion into the connectors. Look for my SUA report for more info.

I recommend if you have a P2138 you replace the wires between the APP sensor and the ECM and replace the APP sensor. No butt connectors or mickey mouse repairs.

The TPS code is involved in a specials campaign.

I have been investigating these codes for over a year in a horrific crash replace the wires correctly please.
 

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