Fuel Pressure Regulator 2 Control Limit Exceeded – Pressure Too High

How severe is this DTC?

Since insufficient/excessive fuel pressure can damage the internal engine and catalytic converter and lead to various driving issues, a P229B code should be classified as severe.

What are some of the symptoms of the code?

Symptoms of a P229B fault code may include:

Engine misfire codes and idle control codes may also accompany a P229B
Reduced fuel efficiency
Delayed starting when the engine is cold
Black smoke from the exhaust system

What are some common causes of the code?

Causes

of this code may include:

The engine is not timed correctly
Low engine oil pressure
Faulty fuel pressure sensor
Faulty fuel pressure regulator
Shorted or open wiring or connectors in the fuel pressure regulator control circuit
Incorrect PCM or PCM programming error

What are the troubleshooting steps for P229B?

You will need a diagnostic scanner, a digital volt/ohmmeter (DVOM), and a reliable source of vehicle information to accurately diagnose a P229B code.

You can save time by looking for Technical Service Bulletins (TSBs) that match the recorded code, the vehicle (year, make, model, and engine), and the symptoms presented. This information can be found in your vehicle information source. If you find the right TSB, it might provide a quick solution to your diagnosis.

After connecting the scanner to the vehicle’s diagnostic port and retrieving all stored codes and relevant freeze frame data, note the information (in case the code turns out to be intermittent). After that, clear the codes and test the vehicle until one of two things happens; the code is restored or the PCM enters readiness mode.

The code may be more difficult to diagnose if the PCM enters readiness mode at this point, as the code is intermittent. The condition that caused the P229B to be stored may need to worsen before an accurate diagnosis can be made. If the code is restored, proceed with the diagnosis.

You can obtain connector face views, connector pinout diagrams, component location diagrams, wiring diagrams, and diagnostic flowcharts (related to the code and the specific vehicle) using your vehicle information source.

Perform a visual inspection of the associated wiring and connectors. Repair or replace any wiring that is cut, burned, or damaged.

Use the DVOM to test the voltage and ground circuits at the electronic fuel regulator (2) and fuel pressure sensors. If no voltage is detected, check the system fuses. Replace any blown or faulty fuses as needed and retest.

If voltage is detected, test the corresponding circuit at the PCM connector. If no voltage is detected there, suspect an open circuit between the sensor in question and the PCM. If voltage is found there, suspect a PCM programming error or faulty PCM.

Test the fuel pressure regulator and fuel pressure sensor with the DVOM. If either does not meet the manufacturer’s specifications, consider it faulty.

If the fuel regulator (2) and sensor(s) appear to be functioning correctly, use a manual pressure gauge to test the actual fuel pressure on the rail to replicate the failure condition.

The fuel rail and associated components may be under (extremely) high pressure
Be cautious when removing the fuel pressure sensor or fuel pressure regulator
Fuel pressure tests should be performed with the ignition switch in the Key On Engine Off (KOEO) position

P229C Fuel Pressure Regulator 2 Learning Limit Exceeded – Too Low

How severe is this DTC?

Since insufficient/excessive fuel pressure can damage the internal engine and catalytic converter and lead to various driving issues, a P229C code should be classified as severe.

What are some of the symptoms of the code?

Symptoms of a P229C fault code may include:

No start condition
Engine misfire codes and idle control codes may also accompany a P229C
Reduced fuel efficiency
Delayed starting when the engine is cold
Black smoke from the exhaust system

What are some common causes of the code?

Causes of this code may include:

Engine timing is incorrect
Low engine oil pressure
Faulty fuel pressure sensor
Faulty fuel pressure regulator
Shorted or open wiring or connectors in the fuel pressure regulator control circuit
Incorrect PCM or PCM programming error

What are the troubleshooting steps for P229C?

You will need a diagnostic scanner, a digital volt/ohmmeter (DVOM), and a reliable source of vehicle information to accurately diagnose a P229C code.

The code may be more difficult to diagnose if the PCM enters readiness mode at this point, as the code is intermittent. The condition that caused the P229C to be stored may need to worsen before an accurate diagnosis can be made. If the code is restored, proceed with the diagnosis.

You can obtain connector face views, connector pinout charts, component location diagrams, wiring diagrams, and diagnostic flowcharts (related to the code and the specific vehicle) using your vehicle information source.

Perform a visual inspection of the associated wiring and connectors. Repair or replace any wiring that is cut, burned, or damaged.

Use the DVOM to test the voltage and ground circuits at the electronic fuel regulator and fuel pressure sensors. If no voltage is detected, check the system fuses. Replace any blown or faulty fuses as needed and retest.

Test the fuel pressure regulator and fuel pressure sensor with the DVOM. If either does not meet the manufacturer’s specifications, consider it faulty.

If the fuel regulator and sensor(s) appear to be functioning correctly, use a manual pressure gauge to test the actual fuel pressure on the rail to replicate the failure condition.

The fuel rail and associated components may be under (extremely) high pressure
Be cautious when removing the fuel pressure sensor or fuel pressure regulator
Fuel pressure tests should be performed with the ignition switch in the Key On Engine Off (KOEO) position

P229D Fuel Pressure Regulator 2 Control Limit Exceeded – Too High

How severe is this DTC?

Since insufficient/excessive fuel pressure can damage the internal engine and catalytic converter and lead to various driving issues, a P229D code should be classified as severe.

What are some of the symptoms of the code?

Symptoms of a P229D fault code may include:

No start condition
Engine misfire codes and idle control codes may also accompany a P229D
Reduced fuel efficiency
Delayed starting when the engine is cold
Black smoke from the exhaust system

What are some common causes of the code?

Causes of this code may include:

Engine timing is incorrect
Low engine oil level/pressure
Faulty fuel pressure sensor
Faulty fuel pressure regulator
Shorted or open wiring or connectors in the fuel pressure regulator control circuit
Incorrect PCM or PCM programming error

What are the troubleshooting steps for P229D?

You will need a diagnostic scanner, a digital volt/ohmmeter (DVOM), and a reliable source of vehicle information to accurately diagnose a P229D code.

The code may be more difficult to diagnose if the PCM enters readiness mode at this point, as the code is intermittent. The condition that caused the P229D to be stored may need to worsen before an accurate diagnosis can be made. If the code is restored, proceed with the diagnosis.

Perform a visual inspection of the associated wiring and connectors. Repair or replace any wiring that is cut, burned, or damaged.

Test the fuel pressure regulator and fuel pressure sensor with the DVOM. If either does not meet the manufacturer’s specifications, consider it faulty.

If the fuel regulator (2) and sensor(s) appear to be functioning correctly, use a manual pressure gauge to test the actual fuel pressure on the rail to replicate the failure condition.

The fuel rail and associated components may be under (extremely) high pressure
Be cautious when removing the fuel pressure sensor or fuel pressure regulator
Fuel pressure tests should be performed with the ignition switch in the Key On Engine Off (KOEO) position

P2100 – Open Throttle Actuator Control Motor Circuit

Code P2100 – Severity, Symptoms, and Repairs

1. Severity of Code P2100

Code P2100 is generally severe due to its direct impact on the Electronic Throttle Control (ETC) system. It is often an electrical issue preventing the Powertrain Control Module (PCM) from fully compensating for the failure.

An engine affected by this code may:
🔧 Have a fixed idle speed (typically between 1000 and 1200 RPM)
🔧 No longer respond to the accelerator, limiting driving

2. Symptoms of Code P2100

Signs indicating a problem with the throttle actuator include:
✅ Malfunction indicator light illuminated (Check Engine)
✅ Engine speed frozen (unable to adjust idle)
✅ No response to acceleration (pedal ineffective)

3. Possible Causes of Code P2100

Common failures that can trigger this code are:
✔️ Open circuit in the throttle actuator – most likely
✔️ Faulty throttle actuator – internal electrical failure
✔️ Defective PCM – unlikely but possible

4. Diagnostic and Repair Procedures

🔍 Step 1: Checking Technical Service Bulletins (TSBs)

First, consult TSBs specific to your vehicle. It may be a known issue with a solution already published by the manufacturer.

🔍 Step 2: Inspecting Wiring and Connectors

📌 Locate the Throttle Actuator A (TA-A). It is often situated:

At the front or top of the engine
Inside the wheel wells
Against the firewall

✔️ Inspect cables and connectors to detect:

Exposed, burnt, or chafed wires
Corroded or melted connections
✔️ Clean terminals with electrical contact cleaner and apply electrical grease.

🔍 Step 3: Clearing Codes and Testing

📌 Clear codes with an OBD2 scanner and restart the engine:

If the code does not return, the problem was likely a poor connection.
If the code returns, continue diagnostics.

🔍 Step 4: Testing the Throttle Actuator

✔️ Disconnect the wiring harness from the throttle actuator.
✔️ With a digital multimeter (DVOM), measure the resistance between the actuator terminals:

A reading of infinity or 0 ohms indicates an open or short circuit → replace the actuator.
Check your vehicle’s resistance specifications to confirm the correct value.

🔍 Step 5: Checking Electrical Power Supply

✔️ With a DVOM, verify that the throttle actuator receives 12V:

Red wire to the actuator power supply
Black wire to ground
✔️ Activate the actuator with an OBD2 diagnostic tool:
No 12V? Repair wiring or check the relay.
12V present but no reaction? The actuator is likely faulty.

🔍 Step 6: Checking Ground

✔️ Use a test light connected to +12V:

Touch the actuator’s ground circuit
If the light does not illuminate → poor ground connection
If the light flickers when shaking the harness → intermittent connection

5. Conclusion

Code P2100 is serious and can prevent the engine from responding to acceleration. The problem is usually electrical and related to the throttle actuator or its circuit.

🚗 If you have checked all tests and the code persists, the actuator is likely defective. A faulty PCM is rare, but if the problem continues after replacing the actuator, PCM reprogramming may be necessary.

⚠️ If you are unsure of the diagnosis, consult a qualified professional.

P2101 – Throttle Actuator A Control Motor Circuit Range Performance

Code Severity and Symptoms

The severity is generally severe due to its impact on the cooling system. Since it could be an electrical or mechanical failure, the PCM cannot fully compensate for it. Partial compensation usually means the engine has a fixed idle speed (typically around 1000 – 1200 RPM).

Symptoms of a P2101 engine code may include:

Malfunction indicator light illuminated
Fixed idle speed
Unable to accelerate the engine

Causes

Typically, the causes for this code to set are as follows:

Open or short circuit in the throttle actuator circuit – likely
Faulty throttle actuator – inoperative (mechanically or electrically) – probable
Failed PCM – unlikely

Diagnostic and Repair Procedures

A good starting point is always to check the Technical Service Bulletins (TSBs) for your specific vehicle. Your issue might be a known problem with a published fix from the manufacturer and could save you time and money during diagnosis.

Next, locate the Throttle Actuator A (TA-A) on your specific vehicle. This actuator is typically mounted on the front of the engine, on top of the engine, inside the wheel wells, or against the firewall. Once located, visually inspect the connector and wiring. Look for scratches, rubbing, exposed wires, burns, or melted plastic. Disconnect the connector and carefully inspect the terminals (the metal parts) inside the connector. Check if they appear burnt or have a greenish tint indicating corrosion. Use electrical contact cleaner and a plastic-bristled brush if terminal cleaning is needed. Let it dry and apply electrical grease where the terminals make contact.

If you have a scan tool, clear the diagnostic codes from memory and see if the P2101 code returns. If it does not, the connections were likely your issue.

For this particular code, this is the most common area of concern, along with relays/connections to relays, with actuator failure being a close second.

If the code returns, we will need to test the actuator and related circuits. Typically, each throttle actuator has 2 wires. First, disconnect the wiring harness going to the throttle actuator. With a digital volt-ohm meter (DVOM), connect one meter lead to one terminal of the actuator. Connect the remaining meter lead to the other terminal of the actuator. It should not be open or shorted. Check the resistance specifications for your specific vehicle. If the actuator motor is open or shorted (infinite resistance or no resistance/0 ohms), replace the throttle actuator.

If this test passes, with a DVOM, verify that you have 12V at the throttle actuator power circuit (red lead to the actuator power circuit, black lead to a good ground). With a scan tool that can activate the throttle actuator, turn on the throttle actuator. If there is no 12 volts at the actuator, repair the wiring from the PCM or relay to the actuator, or possibly a faulty PCM.

If that checks out, ensure you have a good ground at the throttle actuator. Connect a test light to the positive 12V battery (red terminal) and touch the other end of the test light to the ground circuit going to the throttle actuator circuit ground. Using the scan tool to actuate the throttle actuator, check if the test light illuminates each time the scan tool actuates the actuator. If the test light does not illuminate, it would indicate a circuit problem. If it lights up, wiggle the wiring harness going to the actuator to see if the test light flickers, indicating an intermittent connection.

If all previous tests have passed and you continue to get a P2101, it would most likely indicate a faulty throttle actuator, although a defective PCM cannot be ruled out until the throttle actuator has been replaced. If in doubt, seek assistance from a qualified automotive diagnostician. PCMs need to be programmed or calibrated to the vehicle to be installed correctly.

P2102 – Low Value of Throttle Actuator A Control Motor Circuit

Code Severity and Symptoms

The severity is generally severe due to its impact on the cooling system. Since it’s typically an electrical failure, the PCM cannot fully compensate for it. Partial compensation usually means the engine has a fixed idle speed (generally around 1000 – 1200 RPM).

Symptoms of a P2102 engine code may include:

Malfunction indicator light illuminated
Fixed idle speed
Unable to accelerate the engine

Causes

Typically, the causes for this code to set are as follows:

Open or short circuit in the throttle actuator circuit – likely
Failed throttle actuator – likely
Failed PCM – unlikely

Diagnostic and Repair Procedures

A good starting point is always to check the Technical Service Bulletins (TSBs) for your specific vehicle. Your issue might be a known problem with a known fix published by the manufacturer and could save you time and money during diagnosis.

Next, locate the Throttle Actuator A (TA-A) on your specific vehicle. This actuator is typically found mounted on the front of the engine, on top of the engine, inside the wheel wells, or against the firewall. Once located, visually inspect the connector and wiring. Look for chafing, rubbing, bare wires, burns, or melted plastic. Disconnect the connector and carefully inspect the terminals (the metal parts) inside the connector. See if they appear burnt or have a greenish tint indicating corrosion. Use electrical contact cleaner and a plastic bristle brush if cleaning the terminals is necessary. Let it dry and apply electrical grease where the terminals make contact.

If you have a scan tool, clear the diagnostic codes from the memory and see if the P2102 code returns. If it does not, the connections were likely your problem.

For this code, this is the most common area of concern, just like relay/connections to relays, with actuator failure being a close second.

If that checks out, ensure you have a good ground at the throttle actuator. Connect a test light to the positive 12V battery (red terminal) and touch the other end of the test light to the ground circuit going to the throttle actuator circuit ground. Using the scan tool to actuate the throttle actuator, check if the test light illuminates each time the scan tool actuates the actuator. If the test light does not illuminate, it would indicate a circuit problem. If it does illuminate, wiggle the wiring harness going to the actuator to see if the test light flickers, indicating an intermittent connection.

If all previous tests have passed and you continue to get a P2102, it would most likely indicate a failing throttle actuator, although a faulty PCM cannot be ruled out until the throttle actuator has been replaced. If in doubt, seek assistance from a qualified automotive diagnostician. PCMs need to be programmed or calibrated to the vehicle to be installed correctly.

P2103 – High Throttle Actuator Control Motor Circuit

Code Severity and Symptoms

The severity is generally severe due to its impact on the cooling system. Since it is typically an electrical failure, the PCM cannot fully compensate for it. Partial compensation usually means the engine has a fixed idle speed (generally around 1000 – 1200 RPM).

Symptoms of a P2103 engine code may include:

Malfunction indicator light illuminated
Fixed idle speed
Unable to accelerate the engine

Causes

Typically, the causes for this code to set are as follows:

Open in the throttle actuator circuit – likely
Failed throttle actuator – probable
Failed PCM – unlikely

Diagnostic and Repair Procedures

A good starting point is always to check the Technical Service Bulletins (TSBs) for your specific vehicle. Your issue might be a known problem with a known fix released by the manufacturer and could save you time and money during diagnosis.

Next, locate the Throttle Actuator A (TA-A) on your specific vehicle. This actuator is usually mounted on the front of the engine, on top of the engine, inside the wheel wells, or against the firewall. Once located, visually inspect the connector and wiring. Look for scratches, rubbing, bare wires, burns, or melted plastic. Disconnect the connector and carefully inspect the terminals (the metal parts) inside the connector. Check if they appear burnt or have a greenish tint indicating corrosion. Use electrical contact cleaner and a plastic-bristled brush if terminal cleaning is needed. Let it dry and apply electrical grease where the terminals make contact.

If you have a scan tool, clear the diagnostic codes from memory and see if the P2103 code returns. If not, the connections were likely your issue.

For this code, this is the most common area of concern, as are relay/connections to relays, with actuator failure being a close second.

If this test passes, use a DVOM to verify you have 12V at the throttle actuator power circuit (red lead to the actuator power circuit, black lead to a good ground). With a scan tool that can activate the throttle actuator, turn on the throttle actuator. If there is no 12 volts at the actuator, repair the wiring from the PCM or relay to the actuator, or possibly a faulty PCM.

If all previous tests have passed and you continue to get a P2103, it would most likely indicate a failing throttle actuator, although a faulty PCM cannot be ruled out until the throttle actuator has been replaced. If in doubt, seek assistance from a qualified automotive diagnostician. PCMs need to be programmed or calibrated to the vehicle to be installed correctly.

P2104 Throttle Actuator Control System – Forced Idle

Code Severity and Symptoms

The severity of this code can range from moderate to severe depending on the specific malfunction. Symptoms of a P2104 trouble code may include:

Engine does not start
Little or no throttle response
Check engine light illuminated
ABS light illuminated
Automatic transmission won’t shift
Additional codes present

Common Causes of This DTC Code

The most common situations that set this code and put the engine in fail-safe or limp mode to indicate a problem and act as a red flag are:

Engine overheating
Coolant leaks
EGR valve malfunction
Mass airflow sensor malfunction
Engine axle modifications
ABS, traction control, or stability control failures
Automatic transmission problems
Abnormal system voltages

What Are Common Repairs?

Repair coolant leak
Replace or clean ABS sensor
Replace or clean EGR valve
Replace or clean mass airflow sensor
Clean connector corrosion
Repair or replace wiring
Replacing PCM

Diagnostic and Repair Procedures

The first step in troubleshooting any malfunction is to search for Technical Service Bulletins (TSBs) for the specific vehicle by year, model, and powertrain. In some circumstances, this can save you considerable time in the long run by pointing you in the right direction.

The second step for this code is to perform a PCM scan to identify other trouble codes. This code is an informational code and in most cases its function is to alert a driver that the PCM has initiated a fail-safe mode due to a malfunction or failure in a system not directly related to the throttle actuator control.

If other codes are identified, you should check TSBs related to the specific vehicle and that code. If a TSB hasn’t been issued, you should follow the specific troubleshooting steps for that code to identify the source of the malfunction detected by the PCM that caused the engine to enter fail-safe or limp mode.

Once all other codes have been cleared or if no other codes are detected, if the throttle actuator control code still exists, the PCM and throttle actuator must be evaluated. All wiring and connections should be visually inspected for obvious defects as a starting point.

Common Mistake

Replacing the throttle actuator or PCM when other malfunctions are setting this code.

Rare Repair

Replacing the throttle actuator control

I hope the information in this article has been helpful in pointing you in the right direction to fix the issue with your throttle actuator control system force code. This article is strictly informational and specific vehicle technical data and service bulletins should always take priority.

P2105 Throttle Actuator Control System – Forced Engine Shutdown

Code Severity and Symptoms

The severity of this code can range from moderate to severe depending on the specific malfunction. Symptoms of a P2105 trouble code may include:

Engine does not start
Little or no throttle response
Check engine light illuminated
ABS light illuminated
Automatic transmission won’t shift
Additional codes present

Common Causes of This DTC Code

The most common situations that set this code and put the engine in fail-safe or limp mode to indicate a problem and act as a red flag are:

Engine overheating
Coolant leaks
EGR valve malfunction
Mass airflow sensor malfunction
Engine axle modifications
ABS, traction control, or stability control failures
Automatic transmission issues
Abnormal system voltages

What Are Common Repairs?

Repair coolant leak
Replace or clean ABS sensor
Replace or clean EGR valve
Replace or clean mass airflow sensor
Clean connector corrosion
Repair or replace wiring
Flashing or replacing PCM

Diagnostic and Repair Procedures

The first step in troubleshooting any malfunction is to search for Technical Service Bulletins (TSBs) for the specific vehicle by year, model, and powertrain. In some circumstances, this can save significant time in the long run by pointing you in the right direction.

The second step for this code is to perform a PCM scan to identify other trouble codes. This code is an informational code and in most cases functions to alert the driver that the PCM has initiated a fail-safe mode due to a malfunction or failure in a system not directly related to the throttle actuator control.

If other codes are identified, you should check TSBs related to the specific vehicle and that code. If no TSB has been issued, you should follow the specific troubleshooting steps for that code to identify the source of the malfunction detected by the PCM that caused the engine to enter fail-safe or limp mode.

Once all other codes have been cleared or if no other codes are detected, if the throttle actuator control code still exists, the PCM and throttle actuator control must be evaluated. All wiring and connections should be visually inspected for obvious defects as a starting point.

Common Mistake

Replacing the throttle actuator control or PCM when other malfunctions are setting this code.

Rare Repair

Replacing the throttle actuator control assembly

I hope the information in this article has been helpful in guiding you in the right direction to fix the issue with your throttle actuator control system force code. This article is strictly informational and specific technical data and service bulletins for your vehicle should always take priority.

P2106 Throttle Actuator Control System – Forced Limited Power

Code Severity and Symptoms

The severity of this code can range from moderate to severe depending on the specific malfunction. Symptoms of a P2106 trouble code may include:

Engine does not start
Little or no throttle response
Check engine light illuminated
ABS light illuminated
Automatic transmission won’t shift
Additional codes present

Common Causes of This DTC Code

The most common situations that set this code and put the engine in fail-safe or limp mode to indicate a problem and act as a red flag are:

Engine overheating
Coolant leaks
EGR valve malfunction
Mass air flow sensor malfunction
Engine axle modifications
ABS, traction control, or stability control failures
Automatic transmission problems
Abnormal system voltages

What Are the Common Repairs?

Repair coolant leak
Replace or clean ABS sensor
Replace or clean EGR valve
Replace or clean mass air flow sensor
Clean connector corrosion
Repair or replace wiring
PCM replacement

Diagnostic and Repair Procedures

This is an important step, just as an example, some Ford vehicles from 2003 to 2005 are affected by a P2106 and/or other codes and the fix is to reprogram the PCM.

If other codes are identified, you should check TSBs related to the specific vehicle and that code. If a TSB has not been issued, you should follow the specific troubleshooting steps for that code to identify the source of the malfunction detected by the PCM that caused the engine to enter fail-safe or limp mode.

Common Mistake

Replacing the throttle actuator control or PCM when other malfunctions are setting this code.

Rare Repair

Replacing the throttle actuator control

I hope the information in this article has been helpful in pointing you in the right direction to correct the issue with your throttle actuator control system force code. This article is strictly informational and specific technical data and service bulletins for your vehicle should always take priority.