P0120 Code - Throttle / Pedal Position Sensor / Switch 'A' Circuit Malfunction
Quick Answer
The throttle position sensor is mounted on the throttle with motor body assembly and detects the opening angle of the throttle valve. Common causes include Faulty Throttle Position Sensor (built into Throttle Body Assembly), Throttle Position Sensor circuit is open or shorted, Throttle Position Sensor 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
- P0120 indicates Throttle / Pedal Position Sensor / Switch 'A' Circuit Malfunction.
- Common causes
- Common causes include Faulty Throttle Position Sensor (built into Throttle Body Assembly), Throttle Position Sensor circuit is open or shorted, Throttle Position Sensor 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.
Code P0120 Description
As the valve closes, the sensor output voltage decreases and as the valve opens, the sensor output voltage increases. The Engine Control Module (ECM) calculates the throttle valve opening angle according to these signals and controls the throttle actuator in response to driver inputs. These signals are also used in calculations such as air-fuel ratio correction, power increase correction, and fuel-cut control.
The ECM uses the throttle position sensor to monitor the throttle valve opening angle. There are several checks that the ECM performs to confirm the proper operation of the throttle position sensor.
This sensor transmits two signals, if the output voltage difference between the two signals deviates from the normal operating range, the ECM interprets this as a malfunction in the throttle position sensor. The ECM illuminates the MIL and stores the Diagnostic Trouble Code (DTC).
What are the Possible Causes of the DTC P0120?
- Faulty Throttle Position Sensor (built into Throttle Body Assembly)
- Throttle Position Sensor circuit is open or shorted
- Throttle Position Sensor poor electrical connection
- Faulty Engine Control Module (ECM)
How to Fix the DTC P0120?
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 P0120 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.
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Information for Specific Makes
- P0120 Audi — Throttle Pedal Position Sensor/Switch 'A' Circuit Malfunction
- P0120 Buick — Throttle Position Sensor 1 Circuit
- P0120 Cadillac — Throttle Position Sensor 1 Circuit
- P0120 Chevrolet — Throttle Position Sensor 1 Circuit
- P0120 Chrysler — Electronic Throttle Control Motor Performance
- P0120 Dodge — Electronic Throttle Control Motor Performance
- P0120 GMC — Throttle Position Sensor 1 Circuit
- P0120 Hyundai — Throttle/Pedal Position Sensor/Switch 'A' Circuit
- P0120 Infiniti — Throttle Position Sensor Signal Range/Performance
- P0120 Isuzu — Throttle Position Sensor 1 Circuit
- P0120 Jeep — Electronic Throttle Control Motor Performance
- P0120 Lexus — Throttle / Pedal Position Sensor / Switch 'A' Circuit Malfunction
- P0120 Mazda — Throttle Position Sensor Signal Out of Range
- P0120 Mercedes-Benz — Throttle/Pedal Position Sensor/Switch A Circuit Malfunction
- P0120 Mitsubishi — Throttle Position Sensor Circuit Malfunction
- P0120 Nissan — Throttle Position Sensor Signal Range/Performance
- P0120 Pontiac — Throttle Position Sensor 1 Circuit
- P0120 Saturn — Throttle Position Sensor 1 Circuit
- P0120 Scion — Throttle / Pedal Position Sensor / Switch 'A' Circuit Malfunction
- P0120 Toyota — Throttle / Pedal Position Sensor / Switch 'A' Circuit Malfunction
- P0120 Volkswagen — Throttle Pedal Position Sensor/Switch 'A' Circuit
Frequently Asked Questions about P0120 Code
1. What are the common symptoms of OBDII code P0120?
- Common symptoms include issues with acceleration, lack of power, stalling, or the vehicle not responding properly to the gas pedal.
2. What could cause the Throttle/Pedal Position Sensor 'A' Circuit Malfunction code P0120?
- Causes can include a faulty throttle position sensor, damaged wiring or connectors, a faulty accelerator pedal position sensor, or issues with the electronic throttle control system.
3. How can I diagnose the cause of OBDII code P0120?
- Diagnosing may involve visually inspecting wiring and connectors, testing sensor resistance, checking for proper sensor voltage, and using a scan tool to monitor sensor data.
4. Can a dirty throttle body cause code P0120?
- While a dirty throttle body can cause related issues, it is not a direct cause of code P0120. However, it is recommended to clean the throttle body as routine maintenance.
5. Is it safe to drive with OBDII code P0120 active?
- It is generally not recommended to drive with code P0120 active, as it can lead to performance issues and potential safety concerns. It is best to address the underlying problem promptly.
6. How do I repair OBDII code P0120?
- Repair may involve replacing the faulty throttle position sensor, repairing damaged wiring or connectors, replacing the accelerator pedal position sensor, or addressing issues with the electronic throttle control system.
7. Can I reset the OBDII code P0120 without fixing the problem?
- While clearing the code may temporarily turn off the check engine light, the underlying issue causing the code will persist. It is important to address and repair the root cause of the problem.
8. What are the potential long-term effects of ignoring OBDII code P0120?
- Ignoring code P0120 can lead to reduced fuel efficiency, engine performance issues, potential stalling or loss of power while driving, and may cause further damage to engine components over time.
9. How much does it typically cost to repair OBDII code P0120?
- The cost of repair can vary depending on the cause of the code, the necessary parts, and labor costs. It is advisable to consult a mechanic for a proper diagnosis and estimate.
10. Can I fix OBDII code P0120 myself?
- Depending on your skill level and access to tools, you may be able to address some causes of code P0120 yourself, such as replacing a throttle position sensor. However, more complex issues may require professional assistance.
Discuss the causes and fixes for P0120 OBDII Code
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I have replaced the throttle body on my e46 330i but i am still getting a 118 or p0120 code on inpa. Any ideas.
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Never had that problem. Try resetting the Throttle Adaptation. Fount the following information online:
- First, with the key removed, sit in the driver's seat and insert the key.
- Turn the key to position "2". Position "2" is one position before the car engages and starts.
- Wait 10 seconds and then turn the key back to position "0", which is the initial position.
- Once again wait 10 seconds and then start the car up.You should now have your throttle response reset and your driving pattern from this point on
will dictate how your throttle response adapts. -
Thanks for your reply. After replacing with new throttle body I am getting a p1623 code tps adaption. Something to do with voltage not being right. Garage tested all the volts on pedal etc and he says all ok. Ecu seems to not be holding adaptions he thinks so has sent it to get looked at and repaired. You any ideas on this code.
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got stuck in the middle of the road with this issue. i quickly scanned my nissan xtrail and got this error code. i saw ur response and gave it a try and my car was resurrected. thanks Gee. but will it happen again coz dis is the first time i'm experiencing such
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