P1224 – Throttle Position Sensor B Out Of Self Test Range

Urgency and Driving Safety

If your vehicle is displaying the P1224 trouble code, it is generally safe to continue driving in the short term. However, you may experience reduced engine performance, rough idling, or stalling. It is recommended to diagnose and repair the issue as soon as possible to prevent further damage and ensure optimal vehicle performance and fuel efficiency.

Code Details

The P1224 code is a generic powertrain code, meaning it applies to all makes and models of vehicles (1996-newer), although specific repair steps may vary slightly between manufacturers.

This code indicates an intermittent problem with the "B" circuit of the throttle/pedal position sensor or switch. The throttle position sensor (TPS) is a potentiometer that provides a voltage signal to the engine control module (ECM) indicating the throttle valve angle.

Related Parts and Function

The main components involved when the P1224 code is triggered include:

1. Throttle Position Sensor (TPS): Measures the throttle valve opening angle and sends a voltage signal to the ECM.
2. Accelerator Pedal Position Sensor (APPS): Detects the position of the accelerator pedal.
3. Engine Control Module (ECM): Receives signals from the sensors and controls the engine operation.

The TPS and APPS work together to determine the driver's desired engine speed and load. The ECM uses these inputs to adjust fuel injection, ignition timing, and other engine parameters for optimal performance.

Common Causes

1. Faulty throttle position sensor
2. Damaged or corroded wiring and connectors
3. Loose or broken electrical connections
4. Faulty accelerator pedal position sensor
5. Malfunctioning ECM (rare)

Diagnostic Steps

1. Connect an OBD-II scanner and check for other trouble codes. Address any additional codes first.
2. Inspect the wiring and connectors between the TPS, APPS, and ECM for damage, corrosion, or loose connections. Repair as needed.
3. Test the TPS and APPS for proper resistance and voltage output according to manufacturer specifications. Replace if faulty.
4. If the issue persists, perform an ECM reset and retest. If the problem returns, the ECM may be faulty.

Repair Solutions

1. Replace the faulty throttle position sensor
2. Repair or replace damaged wiring and connectors
3. Clean and secure any loose or corroded electrical connections
4. Replace the accelerator pedal position sensor if faulty
5. Replace the ECM if all other components test correctly and the issue persists

Prevention

1. Regularly inspect and clean the throttle body and related sensors
2. Avoid exposing electrical components to moisture or extreme temperatures
3. Address any issues promptly to prevent further damage

Repair Costs

Related Issues and Codes

Other common issues and fault codes that may appear alongside P1224 include:

• P0121: Throttle Position Sensor Circuit Range/Performance Problem
• P0122: Throttle Position Sensor Circuit Low Input
• P0123: Throttle Position Sensor Circuit High Input
• P0221: Throttle Position Sensor "B" Circuit Range/Performance Problem
• P0222: Throttle Position Sensor "B" Circuit Low Input
• P0223: Throttle Position Sensor "B" Circuit High Input
• P2135: Throttle Position Sensor/Accelerator Pedal Position Sensor Voltage Correlation

Repair Guide

1. Locate the throttle position sensor, typically mounted on the throttle body.
2. Disconnect the negative battery cable and remove the sensor electrical connector.
3. Remove the TPS mounting screws (usually 2-3 screws, T20 or T25 Torx).
4. Install the new TPS and secure with the mounting screws (torque to 1.5-2.0 Nm or 13-18 in-lbs).
5. Reconnect the electrical connector and negative battery cable.
6. Clear the trouble codes and test drive the vehicle to verify the repair.

By addressing the P1224 trouble code promptly and following these diagnostic and repair steps, you can restore your vehicle's performance and reliability.

Frequently Asked Questions About P1224 Diagnostic Trouble Code

What does the P1224 code mean?

The P1224 code indicates an intermittent problem with the “B” circuit of the throttle/pedal position sensor or switch. It is a generic powertrain code that applies to all makes and models of vehicles (1996-newer), although specific repair steps may vary slightly between manufacturers.

Is it safe to drive with a P1224 code?

It is generally safe to continue driving in the short term if your vehicle is displaying the P1224 trouble code. However, you may experience reduced engine performance, rough idling, or stalling. It is recommended to diagnose and repair the issue as soon as possible to prevent further damage and ensure optimal vehicle performance and fuel efficiency.

What are the common symptoms of a P1224 code?

Common symptoms associated with the P1224 code include:

• Reduced engine performance
• Rough idling
• Stalling
• Illuminated check engine light
• Poor fuel efficiency

What causes a P1224 code?

The most common causes of a P1224 code are:

1. Faulty throttle position sensor (TPS)
2. Damaged or corroded wiring and connectors
3. Loose or broken electrical connections
4. Faulty accelerator pedal position sensor (APPS)
5. Malfunctioning engine control module (ECM) – rare

How do I diagnose a P1224 code?

To diagnose a P1224 code:

1. Connect an OBD-II scanner and check for other trouble codes. Address any additional codes first.
2. Inspect the wiring and connectors between the TPS, APPS, and ECM for damage, corrosion, or loose connections. Repair as needed.
3. Test the TPS and APPS for proper resistance and voltage output according to manufacturer specifications. Replace if faulty.
4. If the issue persists, perform an ECM reset and retest. If the problem returns, the ECM may be faulty.

Can I replace just the throttle position sensor to fix a P1224 code?

In most cases, the throttle position sensor (TPS) is integrated into the throttle body and cannot be replaced separately. You may need to replace the entire throttle body assembly or have it rebuilt by a professional.

How much does it cost to repair a P1224 code?

The cost to repair a P1224 code varies depending on the specific cause and the make and model of your vehicle. On average, you can expect to pay:

• Throttle Position Sensor: $50-$200 (€45-€180)
• Accelerator Pedal Position Sensor: $100-$300 (€90-€270)
• Wiring and Connectors: $50-$150 (€45-€135)
• ECM (if needed): $500-$1,500 (€450-€1,350)
• Labor: $50-$150 per hour (€45-€135 per hour)

Can a faulty throttle body cause a P1224 code?

Yes, a faulty throttle body can cause a P1224 code. The throttle position sensor is typically integrated into the throttle body assembly. If the throttle body is damaged or malfunctioning, it can trigger the P1224 code.

How do I test a throttle position sensor?

To test a throttle position sensor:

1. Disconnect the TPS electrical connector.
2. Use a multimeter to measure the resistance between the appropriate pins according to manufacturer specifications.
3. Check for smooth resistance changes as you move the throttle plate.
4. Compare your readings to the manufacturer’s specifications. Replace the TPS or throttle body if the readings are out of range or erratic.

Can a weak battery cause a P1224 code?

While a weak battery itself is unlikely to cause a P1224 code, it can lead to issues with the throttle position sensor or other electrical components that may trigger the code. Always ensure your vehicle’s battery is properly charged and in good condition.

How do I reset the ECM after fixing a P1224 code?

To reset the ECM after fixing a P1224 code:

1. Disconnect the negative battery cable for at least 15 minutes.
2. Reconnect the negative battery cable.
3. Start the engine and allow it to idle for a few minutes.
4. Drive the vehicle for at least 10 miles to allow the ECM to relearn the throttle position sensor values.

Can a P1224 code cause transmission problems?

Yes, a P1224 code can cause transmission problems. The throttle position sensor provides input to the engine control module (ECM), which in turn communicates with the transmission control module (TCM). If the TPS signal is incorrect, it can lead to shifting issues, particularly at low speeds or during slow acceleration.

Is it necessary to replace the accelerator pedal position sensor when fixing a P1224 code?

In most cases, replacing the accelerator pedal position sensor (APPS) is not necessary when fixing a P1224 code. However, if the APPS is found to be faulty during diagnostic testing, it should be replaced to ensure proper throttle control and prevent the code from reoccurring.

Can a vacuum leak cause a P1224 code?

While a vacuum leak is not a direct cause of a P1224 code, it can lead to issues with the throttle position sensor or other engine components that may trigger the code. Always inspect your vehicle’s vacuum lines for leaks and repair as needed.

How often should I clean my throttle body to prevent a P1224 code?

To prevent a P1224 code and ensure optimal throttle body performance, it is recommended to clean your throttle body every 30,000 to 50,000 miles (48,000 to 80,000 km) or as specified in your vehicle’s maintenance schedule.

Can a faulty mass airflow sensor cause a P1224 code?

A faulty mass airflow sensor (MAF) is not a direct cause of a P1224 code. However, a malfunctioning MAF can lead to incorrect air/fuel ratios and engine performance issues that may exacerbate problems with the throttle position sensor or other components related to the P1224 code.

Is it possible to diagnose a P1224 code without a scan tool?

While it is possible to diagnose a P1224 code without a scan tool, it is not recommended. A scan tool allows you to read the specific code, clear codes, and view live data from the throttle position sensor and other engine components. This information is crucial for accurate diagnosis and repair.

Can a P1224 code be caused by a software issue?

In rare cases, a P1224 code can be caused by a software issue in the engine control module (ECM). If all other potential causes have been ruled out and the code persists, reprogramming or replacing the ECM may be necessary.

How can I prevent a P1224 code from reoccurring?

To prevent a P1224 code from reoccurring:

1. Regularly

   inspect and clean the throttle body and related sensors

2. Avoid exposing electrical components to moisture or extreme temperatures
3. Address any issues promptly to prevent further damage
4. Follow your vehicle’s recommended maintenance schedule
5. Use high-quality replacement parts if repairs are needed

What should I do if a P1224 code keeps coming back after repairs?

If a P1224 code keeps coming back after repairs:

1. Double-check that all repairs were completed correctly and with high-quality parts.
2. Recheck all wiring and connectors for damage, corrosion, or loose connections.
3. Perform a thorough diagnostic test of the throttle position sensor, accelerator pedal position sensor, and ECM.
4. Consult with a professional mechanic or dealership for further assistance if the issue persists.

By understanding the causes, symptoms, and repair processes associated with a P1224 code, you can quickly diagnose and fix the issue to restore your vehicle’s performance and reliability.