AutoCodes – Infiniti – P0121 Infiniti

P0121 Infiniti Code - Throttle Position Sensor Circuit Range/Performance Problem

Quick Answer

Electric Throttle Control Actuator consists of throttle control motor, throttle position sensor, etc. Common causes include Faulty throttle position sensor, Throttle position sensor harness is open or shorted, Throttle position sensor circuit poor electrical connection. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means: P0121 Infiniti indicates Throttle Position Sensor Circuit Range/Performance Problem.
Common causes: Common causes include Faulty throttle position sensor, Throttle position sensor harness is open or shorted, Throttle position sensor circuit poor electrical connection.
Severity: High - diagnose this code as soon as possible.
Can I drive?: Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

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Code Popularity 4,447

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Intermediate (2 / 3)

What is this?

Table of contents Created and updated by William Orellana on Jun 14, 2020

Description
Step-by-Step Diagnostic Guide
Possible Causes
How To Fix
Cost to Diagnose
Comments
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Code P0121 Infiniti Description

Electric Throttle Control Actuator consists of throttle control motor, throttle position sensor, etc. The throttle position sensor responds to the throttle valve movement. The throttle position sensor has the two sensors. These sensors are a kind of potentiometers which transform the throttle valve position into output voltage, and emit the voltage signal to the ECM. In addition, these sensors detect the opening and closing speed of the throttle valve and feed the voltage signals to the ECM. The ECM
judges the current opening angle of the throttle valve from these signals and the ECM controls the throttle control motor to make the throttle valve opening angle properly in response to driving condition.

OBDII Code P0121 Infiniti - Throttle Position Sensor Circuit Range/Performance Problem - AutoCodes.com — P0121 Infiniti Code - Throttle Position Sensor Circuit Range/Performance Problem

What does this mean?

What are the Possible Causes of the DTC P0121 Infiniti?

Faulty throttle position sensor.
Throttle position sensor harness is open or shorted
Throttle position sensor circuit poor electrical connection
Faulty accelerator pedal position sensor

How to Fix the DTC P0121 Infiniti?

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

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P0121 Infiniti code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.

Need more information about the P0121 Infiniti code?

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Information for Specific Infiniti Models

P0121 2003 Infiniti G35 — Throttle Position Sensor Circuit Range/Performance Problem

About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.