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AutoCodes - Generic - P0121

P0121 Code - Throttle Position Sensor 1 Performance

- Code Popularity: 107,006 Views
- Repair Importance Level: 3/3
- Repair Difficulty Level: 2/3
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What are the Possible Causes of the DTC P0121?

NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
  • Faulty Throttle Body Assembly
  • Throttle Body Assembly harness is open or shorted
  • Throttle Body Assembly circuit poor electrical connection
  • Faulty Engine Control Module (ECM)
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How to Fix the DTC P0121?

Review the 'Possible Causes' mentioned above and visually examine the corresponding wiring harness and connectors. Ensure to check for any damaged components and inspect the connector pins for signs of being broken, bent, pushed out, or corroded.

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What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P0121 code, it typically requires 1.0 hour of labor. The specific diagnosis time and labor rates at auto repair shops can differ based on factors such as the location, make and model of the vehicle, and even the engine type. It is common for most auto repair shops to charge between $75 and $150 per hour.

What are Code Possible Symptoms?

  • Engine Light ON (or Service Engine Soon Warning Light)

Code P0121 Description

The Throttle Body Assembly contains a contact-less inductive throttle position sensing element that is managed by a customized integrated circuit. The throttle position sensor is mounted within the throttle body assembly and is not serviceable. The Engine Control Module (ECM) supplies the throttle body with a 5 V reference circuit, a low reference circuit. The asynchronous signal means communication is only going from the throttle body to the ECM. The throttle body cannot receive data from the ECM over the signal/serial data circuit. The throttle position sensor provides a signal voltage that changes relative to throttle blade angle. The throttle position sensor information is transmitted between the throttle body and the ECM on the signal/serial data circuit. The ECM decodes the serial data signal and is used as voltages for throttle position sensor 1 and 2. The Diagnostic Trouble Code (DTC) will be set when the ECM detects that the throttle position sensor 1 voltage is stuck in range for greater than 1 s.
OBDII Code P0121 - Throttle Position Sensor 1 Performance - AutoCodes.com
P0121 Code - Throttle Position Sensor 1 Performance

Need More Information on the Code?

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Information for Specific Makes

  • P0121 Acura Throttle Position Sensor 'A' Out of Range  📷
  • P0121 Audi Throttle/Pedal Position Sensor/Switch 'A' Circuit Range/Performance
  • P0121 Buick Throttle Position Sensor 1 Performance    📷
  • P0121 Cadillac Throttle Position Sensor 1 Performance    📷
  • P0121 Chevrolet Throttle Position Sensor 1 Performance    📷
  • P0121 Chrysler Throttle Position Sensor 1 Performance
  • P0121 Dodge Throttle Position Sensor 1 Performance
  • P0121 Ford Throttle/Pedal Position Sensor/Switch 'A' Circuit Range/Performance
  • P0121 GMC Throttle Position Sensor 1 Performance    📷
  • P0121 Honda Throttle Position Sensor 'A' Out of Range    📷
  • P0121 Hummer Throttle Position Sensor 1 Performance
  • P0121 Hyundai Throttle/Pedal Position Sensor/Switch 'A' Circuit Range/Performance
  • P0121 Infiniti Throttle Position Sensor Circuit Range/Performance Problem
  • P0121 Isuzu Throttle Position Sensor 1 Performance
  • P0121 Jaguar Throttle/Pedal Position Sensor/Switch 'A' Circuit Range/Performance
  • P0121 Jeep Throttle Position Sensor 1 Performance
  • P0121 KIA Throttle Position Sensor Circuit Range/Performance Problem
  • P0121 Lexus Throttle / Pedal Position Sensor / Switch 'A' Circuit Range / Performance  📷
  • P0121 Mazda Throttle Position Sensor Malfunction
  • P0121 Mercedes-Benz Throttle/Pedal Position Sensor/Switch A Circuit Range/Performance Problem
  • P0121 Mitsubishi Throttle/Pedal Position Sensor/Switch 'A' Circuit Range/Performance
  • P0121 Nissan Throttle Position Sensor Circuit Range/Performance Problem
  • P0121 Pontiac Throttle Position Sensor 1 Performance
  • P0121 Saturn Throttle Position Sensor 1 Performance
  • P0121 Scion Throttle / Pedal Position Sensor / Switch 'A' Circuit Range / Performance  📷
  • P0121 Subaru Throttle/Pedal Position Sensor/Switch 'A' Circuit Range/Performance
  • P0121 Toyota Throttle / Pedal Position Sensor / Switch 'A' Circuit Range / Performance    📷
  • P0121 Volkswagen Throttle/Pedal Position Sensor/Switch 'A' Circuit Range/Performance
  • P0121 Volvo Throttle/Pedal Position Sensor/Switch 'A' Circuit Range/Performance

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Code P0121 comments

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