AutoCodes – Toyota – P0121 2007 Toyota Prius

P0121 2007 Toyota Prius Code - Throttle/Pedal Position Sensor/Switch 'A' Circuit Range/Performance

Quick Answer

The throttle position sensor (TPS) responds to the accelerator pedal movement. 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 2007 Toyota Prius indicates Throttle/Pedal Position Sensor/Switch 'A' Circuit Range/Performance.
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.

Save to My Repairs Step-by-Step Diagnostic Guide My Repairs

AI answers can be wrong. Verify repairs with testing. Open full chat

Code Popularity 12,712

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
FAQs
Comments
Add Comment

💬 Need more help? Ask Coddy for instant answers — it's free!

Code P0121 2007 Toyota Prius Description

The throttle position sensor (TPS) responds to the accelerator pedal movement. This sensor is a kind of potentiometer which transforms the throttle position into output voltage, and emits the voltage signal to the Engine Control Module (ECM). In addition, the sensor detects the opening and closing speed of the throttle valve and feeds the voltage signal to the ECM.
Idle position of the throttle valve is determined by the ECM receiving the signal from the throttle position sensor. This sensor controls engine operation such as fuel cut. On the other hand, the Wide open and closed throttle position switch, which is built into the throttle position sensor unit, is not used for engine control.

OBDII Code P0121 2007 Toyota Prius - Throttle/Pedal Position Sensor/Switch 'A' Circuit Range/Performance - AutoCodes.com — P0121 2007 Toyota Prius Code - Throttle/Pedal Position Sensor/Switch 'A' Circuit Range/Performance

What does this mean?

What are the Possible Causes of the DTC P0121 2007 Toyota Prius?

Faulty throttle position sensor
Throttle position sensor harness is open or shorted
Throttle position sensor circuit poor electrical connection
Faulty Engine Control Module (ECM)

How to Fix the DTC P0121 2007 Toyota Prius?

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 2007 Toyota Prius 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 2007 Toyota Prius code?

Need more information on how to fix the P0121 2007 Toyota Prius code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P0121 2007 Toyota Prius code diagnosed by a professional: Find a repair shop in your area

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.

Frequently Asked Questions about P0121 2007 Toyota Prius Code

1. What are the common symptoms of OBDII code P0121 on a 2007 Toyota Prius?

The common symptoms include issues with acceleration, lack of power, engine stalling, and the vehicle going into limp mode.

2. What does the OBDII code P0121 indicate for a 2007 Toyota Prius?

The code P0121 indicates an issue with the Throttle/Pedal Position Sensor/Switch 'A' Circuit Range/Performance on the Prius.

3. What are the possible causes of OBDII code P0121 on a 2007 Toyota Prius?

Possible causes include a faulty throttle position sensor, damaged wiring or connectors, throttle body issues, or a problem with the engine control module (ECM).

4. How can I diagnose the OBDII code P0121 on my 2007 Toyota Prius?

Diagnosing the code involves checking the throttle position sensor's voltage, inspecting the wiring and connectors for damage, and scanning the ECM for any related error codes.

5. Can I still drive my 2007 Toyota Prius with OBDII code P0121?

It is not recommended to drive the vehicle with code P0121 as it can lead to unsafe driving conditions and potential further damage to the engine.

6. How can I repair OBDII code P0121 on my 2007 Toyota Prius?

Repairing the issue may involve replacing the throttle position sensor, repairing damaged wiring or connectors, cleaning the throttle body, or reprogramming the ECM.

7. Will resetting the OBDII code P0121 on my 2007 Toyota Prius make it go away permanently?

Resetting the code may temporarily clear the warning light, but if the underlying issue causing P0121 is not addressed, the code is likely to reappear.

8. Can a DIY enthusiast fix OBDII code P0121 on a 2007 Toyota Prius?

Depending on the level of expertise, a DIY enthusiast may be able to diagnose and repair P0121 by following a repair manual or online guides, but professional help is recommended for complex issues.

9. How much does it typically cost to repair OBDII code P0121 on a 2007 Toyota Prius?

The cost of repairs can vary depending on the exact cause of the issue, but it may range from $100 for a simple fix like sensor replacement to $500 or more for more complex repairs involving the throttle body or ECM.

10. Can OBDII code P0121 on a 2007 Toyota Prius cause long-term damage if left untreated?

Yes, leaving the issue unresolved can lead to further damage to the engine and other components over time, so it is important to address code P0121 promptly.