What does it mean?

This DTC is a generic powertrain code that applies to all turbocharged or supercharged vehicles.

The Powertrain Control Module (PCM) controls and monitors both the boost pressure and if the measured pressure is higher than the commanded pressure, DTC P0240 will be set and the PCM will illuminate the Check Engine light. To diagnose this code, you need to have a general understanding of three things:

What is boost pressure?
How is it controlled?
How is it measured?

In a normally aspirated engine (i.e., non-turbo), the downward movement of the pistons, called the intake stroke, creates a vacuum in the intake manifold in the same way a syringe draws in liquid. This vacuum is how the air/fuel mixture is drawn into the combustion chamber. A turbocharger is a pump driven by exhaust gases as they exit the combustion chamber. This creates pressure in the intake manifold. So, instead of the engine having to “suck” in the air/fuel mixture, it is instead force-fed a larger volume. In essence, there is already compression before the piston begins its compression stroke, which increases compression and thus increases power. This is boost pressure.

Boost pressure is controlled by the amount of exhaust gas allowed to pass through the turbo. The higher the amount, the faster the turbo spins, the higher the boost pressure. Exhaust gases are routed around the turbo via a bypass known as a wastegate. The PCM controls the boost pressure by regulating the opening of the bypass. It does this by opening or closing the wastegate as needed. This is accomplished by means of a vacuum motor mounted on or near the turbo. The PCM controls the amount of vacuum going to the vacuum motor via a control solenoid.

The actual pressure in the intake manifold is measured either by a boost pressure sensor (Ford/VW) or a manifold absolute pressure sensor (Chrysler/GM). The different sensor types represent the different technical description given by each manufacturer, but both perform the same function.

This particular code should be addressed as soon as possible due to the increased risk of overboost and damage to the catalyst.

Symptoms

When the conditions for setting P0240 are present, the PCM ignores the actual manifold pressure readings and uses an assumed or presumed manifold pressure, limits the amount of fuel and dynamic injection timing allowed. The PCM enters what is called Failure Mode Engine Management (FMEM) and is most noticeably characterized by a lack of power.

Causes

Causes

possible causes for setting this code are as follows:

Vacuum supply
Pinched, collapsed, or broken vacuum lines
Faulty control solenoid
Faulty PCM

Diagnostic and Repair Procedures

A good starting point is always to check the Technical Service Bulletins (TSBs) for your particular vehicle. Your problem may be a known issue with a known fix published by the manufacturer and can save you time and money when diagnosing.

Visually inspect vacuum lines for kinks, pinches, cracks, or breaks. Check all lines, not just those related to “B” wastegate control. A significant leak anywhere in the vacuum system can lead to poor performance of the entire system. If this checks out, proceed to step 2.
Using a vacuum gauge, check the vacuum on the inlet side of the “B” control solenoid. If none is present, suspect a faulty vacuum pump. If vacuum is present, proceed to step 3.
The control solenoid is actuated by pulse width modulation or duty cycle. Using a digital volt ohmmeter, which has a duty cycle or frequency setting, probe the signal wire at the solenoid connector. Drive the vehicle and check that a signal appears on the DVOM. If the signal is present, suspect a faulty control solenoid. If no signal is present, suspect a faulty PCM.

What does it mean?

This is a generic powertrain diagnostic trouble code (DTC) applicable to all turbocharged or supercharged vehicles. Brands may include, but are not limited to, Audi, Nissan, Mitsubishi, Mazda, VW, etc.

 

The Powertrain Control Module (PCM) monitors boost pressure with a sensor called the Manifold Absolute Pressure (MAP) sensor. Understanding how a MAP sensor works is the first step in explaining the cause of P0241.

The PCM sends a 5-volt reference signal to the MAP sensor, and the MAP sensor returns a variable voltage signal to the PCM. When boost pressure is high, the voltage signal is high. When boost pressure is low, the voltage is low. The PCM uses the boost control solenoid to control the amount of boost pressure produced by the turbocharger while using the boost pressure sensor to verify that the boost pressure is correct.

This code is set when the PCM detects a low voltage signal indicating low boost pressure when a high-pressure command has been sent to the “B” boost control solenoid.

Symptoms

Symptoms of a P0241 code may include:

    Check Engine Light will be illuminated
    Low engine power
    Reduced fuel economy

Due to the increased risk of damage to the catalytic converter and turbo overboost when P0241 is present, it should be repaired before continuing to use the vehicle.

Causes

Causes

Possible causes for this code being set are:

    Faulty “B” boost sensor
    Faulty turbocharger
    Faulty PCM
    Wiring issue

Diagnostic and Repair Procedures

Before diagnosing P0241, ensure no other fault codes are present in the PCM’s memory. If there are other DTCs present, they should be checked first. Any codes related to wastegate control or the 5-volt reference will induce the conditions necessary to set this code. In my experience, the PCM is the least likely cause of this issue. More often than not, it is chafed or burned wires near the turbocharger causing shorts or opens in the circuit.

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

    A thorough visual inspection is crucial when trying to resolve this particular DTC. I have seen faulty connections or defective wiring be the root of the problem more than anything else. Disconnect the connectors from the “B” boost sensor and the “B” boost control solenoid and carefully inspect the contact terminals (the metal parts inside the plastic plug) for signs of corrosion. Use a silicone dielectric compound on all connections when reassembling.
    Turn the ignition key with the engine off (KOEO), probe the boost sensor reference wire at the sensor connector with a digital voltmeter (DVOM) for a 5-volt check. If the voltage is correct, the boost sensor signal wire should read between 0.2 volts and 0.5 volts. If it is correct, proceed to the next step; if not, suspect a faulty boost sensor.
    Leave the DVOM connected and start the engine, and using a hand vacuum pump, apply vacuum to the turbocharger wastegate actuator. The voltage should increase; if it does, suspect a faulty PCM; if not, suspect a faulty turbocharger.

Diagnostic Trouble Code (DTC) P0242 Turbocharger/Supercharger Boost Sensor B Circuit High is a generic code applicable to most vehicles equipped with a turbocharger, including brands such as VW, Dodge, Mercedes, Isuzu, Chrysler, Jeep, etc.

Boost System Operation

The Powertrain Control Module (PCM) regulates turbocharger pressure via a boost solenoid. To adjust this pressure, the PCM monitors in real-time the data sent by the boost pressure sensor.

How Does the Boost Sensor Work?

This sensor acts as a variable resistor:

• The PCM sends a 5V reference signal to the sensor.
• When pressure is low, resistance is high → only a low voltage (approximately 0.5V) is returned to the PCM.
• When pressure increases, resistance decreases → the voltage returned to the PCM increases (up to 4.5V at maximum boost).

Code P0242 triggers when the PCM detects a voltage above 4V on the sensor “B” circuit, while no boost is requested.

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Common Symptoms

When this code appears:
✅ Check Engine Light (CEL) illuminates.
✅ The PCM enters limp mode (limited boost and timing).
✅ Noticeable loss of power (vehicle in “safe mode”).
⚠️ Risk of catalytic converter damage if the problem persists.

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Possible Causes

1️⃣ Other associated DTCs (e.g., faulty IAT sensor, ECT sensor, or 5V circuit).
2️⃣ Wiring problem (damaged wires, corroded connectors).
3️⃣ Faulty boost sensor “B”.
4️⃣ Short to voltage in the sensor circuit.
5️⃣ Faulty PCM (less common).

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Diagnostic Procedures

🔧 1. Check Technical Service Bulletins (TSB)
Some vehicles have known issues with solutions published by the manufacturer.

🔧 2. Inspect for intermittent faults (wiggle test)

• With engine running, gently shake the sensor harness to detect poor contact.

🔧 3. Electrical measurements (digital multimeter)

• KOEO (Key On, Engine Off):
  • Disconnect the sensor → check for 5V on the supply.
  • If 5V is absent → PCM or circuit problem.
• Sensor connected:
  • Normal KOEO voltage ≈ 0.5V. If abnormal → faulty sensor.

⚠️ To avoid:
❌ Do not use an incandescent test light (risk of damaging the circuit).

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Conclusion

Code P0242 indicates a high voltage signal problem with the boost sensor. A methodical check of the wiring, sensor, and associated codes is essential to resolve the issue effectively. If the diagnosis is uncertain, further analysis with a specialized scan tool may be necessary.

🚗 Recommended quick solution: Replace the faulty sensor or repair the circuit as needed.

What does it mean?

This generic powertrain/engine diagnostic code generally applies to turbocharged and supercharged engines, including but not limited to certain Audi, Ford, GM, Mercedes, Mitsubishi, VW, and Volvo vehicles.

The Powertrain Control Module (PCM) controls the boost pressure in a gasoline or diesel engine by managing the output circuit to the wastegate/boost control solenoid valve “A”.

Whenever there is an electrical issue with this circuit that it cannot otherwise identify, the PCM will set the P0243 code. This code is considered an electrical circuit fault only.

Troubleshooting steps may vary depending on the manufacturer, the type of wastegate/boost pressure control, and the color of the control solenoid wires.

Symptoms

Symptoms of a P0243 engine code may include:

Malfunction Indicator Light illuminated
Instrument cluster message alerting the driver to the condition
Lack of power

Causes

Causes

Possible reasons for setting this code are as follows:

Open in the control circuit (ground circuit) between the wastegate/boost control solenoid valve A and the PCM
Open in the power supply circuit between the wastegate/boost control solenoid valve A and the PCM
Short to ground in the power supply circuit of the wastegate/boost control solenoid valve A
Wastegate/boost control solenoid valve A
Possibly a failed PCM (highly unlikely)

Diagnostic and Repair Procedures

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

Next, locate the wastegate/boost control solenoid on your specific vehicle. Once located, visually inspect the connectors and wiring. Look for scratches, rubbing, exposed wires, burns, or melted plastic. Separate the connectors and carefully inspect the terminals (the metal parts) inside the connectors. 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 memory and see if P0243 returns. If not, the connections were likely your problem.

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

If this test passes, with a DVOM, ensure you have 12V on the wastegate/boost control solenoid power supply circuit (red lead to the solenoid power supply circuit, black lead to a good ground). Make sure the ignition is on. If there is no 12 volts at the solenoid, or if there is 12 volts when the ignition is off, repair the wiring from the PCM or relay to the solenoid, or possibly a faulty PCM.

If that is okay, check that the wastegate/boost control solenoid is properly grounded. Connect a test light to the 12V battery positive (red terminal) and touch the other end of the test light to the ground circuit going to the wastegate/boost control solenoid circuit ground. Using the scan tool to activate the wastegate/boost control solenoid, check if the test light illuminates each time the scan tool activates the solenoid. If the test light does not illuminate, it would indicate a circuit problem. If it illuminates, wiggle the wiring harness going to the solenoid to see if the test light flickers, indicating an intermittent connection.

If all tests have passed so far and you continue to get a P0243 code, it would most likely indicate a faulty wastegate/boost control solenoid, although a faulty PCM cannot be ruled out until the solenoid 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.

What does error code P0244 mean?

The diagnostic code P0244 is a generic powertrain/engine code. It generally applies to vehicles equipped with turbocharged and supercharged engines, including, but not limited to, certain models from Ford, Mercedes, and Subaru.

The Powertrain Control Module (PCM) regulates the boost pressure in a gasoline or diesel engine by controlling the output circuit to the “A” Wastegate/Supercharger Bypass Valve Control Solenoid.

The P0244 code is stored by the PCM when it detects a problem with the overall boost control operating range or boost-related performance that cannot be attributed to other circuit fault codes. This code can indicate a fault in the electrical circuit or a mechanical problem with the engine, depending on the exact nature of the issue.

It is important to note that troubleshooting steps can vary significantly depending on the vehicle manufacturer, the type of wastegate/supercharger boost pressure control system used, and the color of the control solenoid wires.

Possible symptoms of code P0244

Symptoms associated with a P0244 engine code may include:

• The Malfunction Indicator Lamp (MIL or Check Engine Light) is illuminated.
• A message may appear on the dashboard (instrument cluster) to alert the driver of the problem.
• Lack of engine power.

Potential causes of code P0244

Several factors can lead to this code being stored:

• Open circuit (break) in the control circuit (ground circuit) between the “A” Wastegate/Supercharger Bypass Valve Control Solenoid and the PCM.
• Open circuit (break) in the power supply circuit between the “A” Wastegate/Supercharger Bypass Valve Control Solenoid and the PCM.
• Short to ground in the power supply circuit of the “A” Wastegate/Supercharger Bypass Valve Control Solenoid.
• Short to power in the power supply circuit of the “A” Wastegate/Supercharger Bypass Valve Control Solenoid.
• Faulty “A” Wastegate/Supercharger Bypass Valve Control Solenoid.
• PCM (Powertrain Control Module) failure (although this is considered very unlikely).

Diagnostic and repair procedures

The first recommended step is to check the Technical Service Bulletins (TSBs) specific to your vehicle. The manufacturer may have published information regarding a known issue and a solution, which could save you time and money.

Next, locate the “A” Wastegate/Supercharger Bypass Valve Control Solenoid on your vehicle. Once located, perform a visual inspection of the associated connectors and wiring. Look for signs of rubbing, scraping, bare wires, burning, or melted plastic. Disconnect the connectors and carefully inspect the metal terminals inside. Check if they are burnt or show a greenish discoloration indicating corrosion. If terminal cleaning is necessary, use an electrical contact cleaner and a plastic-bristled brush. Let it dry and apply dielectric grease to the terminals before reconnecting.

The author emphasizes that the most common cause of this code is often related to electrical connection or vacuum problems.

If you have a scan tool (OBD-II scanner), clear the fault codes from the PCM’s memory and observe if the P0244 code returns. If it does not, the problem was likely related to a poor connection.

If the code reappears, it will be necessary to test the solenoid and its associated circuits. Generally, the wastegate/supercharger bypass valve control solenoid has two wires.

1. Solenoid Test: Disconnect the solenoid connector. Using a digital multimeter (DVOM) set to ohms, connect the probes to the two terminals of the solenoid. The solenoid should not be open (infinite resistance) or shorted (zero or very low resistance). Consult the resistance specifications for your specific vehicle. If the solenoid is open or shorted, replace it.

2. Power Supply Check: With the ignition ON and using the DVOM set to volts, check if approximately 12 volts is present on the solenoid’s power supply circuit (red multimeter lead on the solenoid’s power supply wire, black lead on a good vehicle ground). If no voltage is present, or if voltage is present when the ignition is OFF, there may be a wiring problem between the PCM or a relay and the solenoid, or potentially a faulty PCM.

3. Ground Check: To check the solenoid’s ground, connect a test light to the positive (+) terminal of the battery (red terminal) and touch the other end of the test light to the solenoid’s ground circuit. Using the scan tool, activate the wastegate/supercharger bypass valve control solenoid. The test light should illuminate each time the scan tool activates the solenoid. If the test light does not illuminate, this indicates a problem in the ground circuit. If it does illuminate, wiggle the wiring harness going to the solenoid to see if the light flickers, which would indicate an intermittent connection.

4. Mechanical and Vacuum Check (if applicable): Ensure all associated mechanical components are properly secured and operate freely. If the system uses vacuum to actuate the valve, verify that there is sufficient vacuum at the control solenoid. If not, locate the source of the blockage or leak in the vacuum circuit.

If all previous tests are conclusive and the P0244 code persists, it is likely that the wastegate/supercharger boost pressure control solenoid is faulty. Although a faulty PCM is unlikely, it cannot be completely ruled out until the solenoid has been replaced. If in doubt, it is recommended to consult a qualified automotive technician. PCMs often require specific vehicle programming or calibration to function correctly after replacement.

What does it mean?

This generic powertrain/engine diagnostic code generally applies to turbocharged and supercharged engines, including but not limited to some Audi, Ford, GM, Mercedes, Mitsubishi, VW, and Volvo vehicles.

The Powertrain Control Module (PCM) controls the boost pressure in a gasoline or diesel engine by managing the output circuit to the wastegate/boost control solenoid valve “A”.

Depending on how the manufacturer activates the solenoid, when the PCM provides power or ground to energize the solenoid and the PCM detects that there is no voltage in the circuit at any time when there should be (off), the PCM will set the P0245 code. This code is considered an electrical circuit fault only.

Troubleshooting steps may vary depending on the manufacturer, the type of wastegate/boost pressure control, and the color of the control solenoid wires.

Symptoms

Symptoms of a P0245 engine code may include:

Malfunction indicator light illuminated
Instrument cluster message alerting the driver to the condition
Lack of power

Causes

Causes

Possible reasons for setting this code are as follows:

Open in the control circuit (ground circuit) between the wastegate/boost control solenoid valve A and the PCM
Open in the power supply circuit between the wastegate/boost control solenoid A and the PCM
Short to ground in the power supply circuit of the wastegate/boost control solenoid A
Wastegate/boost control solenoid valve A
Possibly a failed PCM (highly unlikely)

Diagnostic and Repair Procedures

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

Next, locate the “A” wastegate/boost control solenoid on your specific vehicle. Once located, visually inspect the connectors and wiring. Look for scratches, rubbing, bare wires, burns, or melted plastic. Separate the connectors and carefully inspect the terminals (the metal parts) inside the connectors. 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. Allow to dry and apply electrical grease where the terminals make contact.

The most common failure is due to connection problems.

If you have a scan tool, clear the diagnostic codes from the memory and see if P0245 returns. If not, the connections were likely your problem.

If the code returns, we will need to test the solenoid and its associated circuits. Typically, there are 2 wires to the wastegate/boost control solenoid. First, disconnect the wiring harness going to the wastegate/boost control solenoid. With a digital volt ohm meter (DVOM), connect one meter lead to one terminal of the solenoid. Connect the remaining meter lead to the other terminal of the solenoid. It should not be open or shorted. Check the resistance specifications for your specific vehicle. If the solenoid is open or shorted (infinite resistance or no resistance/0 ohms), replace the solenoid.

If this test passes, with a DVOM, ensure you have 12V on the wastegate/boost control solenoid power circuit (red lead to the solenoid power circuit, black lead to a good ground). Make sure the ignition is on. If there is no 12 volts at the solenoid, or if there is 12 volts when the ignition is off, repair the wiring from the PCM or relay to the solenoid, or possibly a faulty PCM.

If that is okay, check that the wastegate/boost control solenoid is properly grounded. Connect a test light to the 12V battery positive (red terminal) and touch the other end of the test light to the ground circuit going to the wastegate/boost control solenoid circuit ground. Using the scan tool to activate the wastegate/boost control solenoid, check if the test light illuminates each time the scan tool activates the solenoid valve. If the test light does not illuminate, it would indicate a circuit problem. If it lights up, wiggle the wiring harness going to the solenoid to see if the test light flickers, indicating an intermittent connection.

If all tests have passed so far and you continue to get a P0245 code, it would most likely indicate a failing wastegate/boost control solenoid, although a faulty PCM cannot be ruled out until the solenoid 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.

What does it mean?

This generic powertrain/engine diagnostic code generally applies to turbocharged and supercharged engines, including but not limited to some Audi, Ford, GM, Mercedes, Mitsubishi, VW, and Volvo vehicles.

The Powertrain Control Module (PCM) controls the boost pressure in a gasoline or diesel engine by managing the output circuit to the wastegate/boost control solenoid valve “A”.

 

Depending on how the manufacturer activates the solenoid, when the PCM provides power or ground to energize the solenoid and the PCM detects that voltage is already present in a circuit where it shouldn’t be, the PCM will set code P0246. This code is considered an electrical circuit fault only.

Troubleshooting steps may vary depending on the manufacturer, the type of wastegate/boost pressure control, and the color of the control solenoid wires.

Symptoms

Symptoms of a P0246 engine code may include:

    Malfunction Indicator Light illuminated
    Instrument cluster message alerting the driver to the condition
    Lack of power

Causes

Causes

Possible reasons for setting this code include:

    Open in the control circuit (ground circuit) between the wastegate/boost control solenoid valve A and the PCM
    Open in the power supply circuit between the wastegate/boost control solenoid A and the PCM
    Short to power in the control circuit (power-controlled circuit) between the wastegate/boost control solenoid A and the PCM
    Wastegate/boost control solenoid valve A
    Possibly a failed PCM (highly 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, which could save you time and money during diagnosis.

Next, locate the “A” wastegate/boost control solenoid on your specific vehicle. Once located, visually inspect the connectors and wiring. Look for scratches, rubbing, exposed wires, burns, or melted plastic. Disconnect the connectors and carefully inspect the terminals (the metal parts) inside the connectors. 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 necessary. Allow it to dry and apply electrical grease where the terminals make contact.

The most common failure is due to connection issues.

If you have a scan tool, clear the diagnostic codes from memory and see if P0246 returns. If it does not, the connections were likely your problem.

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

If this test passes, use a DVOM to ensure there is 12V on the wastegate/boost control solenoid power circuit (red lead to the solenoid power circuit, black lead to a good ground). Make sure the ignition is on. If there is no 12 volts at the solenoid, or if there is 12 volts when the ignition is off, repair the wiring from the PCM or relay to the solenoid, or possibly a faulty PCM.

If that is okay, check that the wastegate/boost control solenoid is properly grounded. Connect a test light to the 12V battery positive (red terminal) and touch the other end of the test light to the ground circuit going to the wastegate/boost control solenoid circuit ground. Using the scan tool to activate the wastegate/boost control solenoid, check if the test light illuminates each time the scan tool activates the solenoid valve. If the test light does not illuminate, it would indicate a circuit problem. If it lights up, wiggle the wiring harness going to the solenoid to see if the test light flickers, indicating an intermittent connection.

If all tests have passed so far and you continue to get a P0246 code, it would most likely indicate a failing wastegate/boost control solenoid, although a faulty PCM cannot be ruled out until the solenoid 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.

What does it mean?

This generic powertrain/engine diagnostic code generally applies to turbocharged and supercharged engines, including but not limited to some Audi, Ford, GM, Mercedes, Mitsubishi, VW, and Volvo vehicles.

The Powertrain Control Module (PCM) controls the boost pressure in a gasoline or diesel engine by managing the output circuit to the wastegate/boost pressure control solenoid valve “B”.

Whenever there is an electrical issue with this circuit that it cannot otherwise identify, the PCM will set the P0247 code. This code is considered an electrical circuit fault only.

Troubleshooting steps may vary depending on the manufacturer, the type of wastegate/boost pressure control, and the color of the control solenoid wires.

Symptoms

Symptoms of a P0247 engine code may include:

Malfunction Indicator Light (MIL) illuminated
Instrument cluster message alerting the driver to the condition
Lack of power

Causes

Possible causes for setting this code are as follows:

Open in the control circuit (ground circuit) between the wastegate/boost pressure control solenoid B and the PCM
Open in the power supply circuit between the wastegate/boost pressure control solenoid B and the PCM
Short to ground in the power supply circuit of the wastegate/boost pressure control solenoid B
Faulty wastegate/boost pressure control solenoid B
Possibly a failed PCM (highly unlikely)

Diagnostic and Repair Procedures

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

Next, locate the wastegate/boost pressure control solenoid on your specific vehicle. Once located, visually inspect the connectors and wiring. Look for scratches, rubbing, exposed wires, burns, or melted plastic. Disconnect the connectors and carefully inspect the terminals (the metal parts) inside the connectors. See if they appear burnt or have a greenish tint indicating corrosion. Use electrical contact cleaner and a plastic-bristled 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 P0247 returns. If it does not, the connections were likely your problem.

If the code returns, we will need to test the solenoid and its associated circuits. Typically, there are 2 wires to the wastegate/boost pressure control solenoid. First, disconnect the wiring harness going to the wastegate/boost pressure control solenoid. With a digital volt ohm meter (DVOM), connect one meter lead to one terminal of the solenoid. Connect the remaining meter lead to the other terminal of the solenoid. It should not be open or shorted. Check the resistance specifications for your specific vehicle. If the solenoid is open or shorted (infinite resistance or no resistance / 0 ohms), replace the solenoid.

If this test passes, with a DVOM, ensure you have 12V at the wastegate/boost pressure control solenoid power supply circuit (red lead to the solenoid power supply circuit, black lead to a good ground). Make sure the ignition is on. If there is no 12 volts at the solenoid, or if there is 12 volts when the ignition is off, repair the wiring from the PCM or relay to the solenoid, or possibly a faulty PCM.

If that is okay, check that the wastegate/boost pressure control solenoid is properly grounded. Connect a test light to the 12V battery positive (red terminal) and touch the other end of the test light to the ground circuit going to the wastegate/boost pressure control solenoid circuit ground. Using the scan tool to activate the wastegate/boost pressure control solenoid, check if the test light illuminates each time the scan tool activates the solenoid. If the test light does not illuminate, this would indicate a circuit problem. If it does illuminate, wiggle the wiring harness going to the solenoid to see if the test light flickers, indicating an intermittent connection.

If all tests have passed so far and you continue to get a P0247 code, this would most likely indicate a failing wastegate/boost pressure control solenoid, although a faulty PCM cannot be ruled out until the solenoid has been replaced. If in doubt, seek assistance from a qualified automotive diagnostician. PCMs must be programmed or calibrated to the vehicle to be installed correctly.

What does it mean?

This generic powertrain/engine diagnostic code generally applies to turbocharged and supercharged engines, including but not limited to certain Ford, Mercedes, and Subaru vehicles.

The Powertrain Control Module (PCM) controls the boost pressure in a gasoline or diesel engine by managing the output circuit to the “B” wastegate/boost control solenoid.

Whenever there is an issue with the total boost range or engine performance that cannot be attributed to other circuit failures, the PCM will set the P0248 code. This code can indicate an electrical circuit fault or a mechanical engine problem, depending on the specific issue.

Troubleshooting steps may vary depending on the manufacturer, the type of wastegate/boost pressure control, and the color of the control solenoid wires.

Symptoms

Symptoms of a P0248 engine code may include:

    Malfunction indicator light illuminated
    Instrument cluster message alerting the driver to the condition
    Lack of power

Causes

Possible causes for this code being set include:

    Open in the control circuit (ground circuit) between the wastegate/boost control solenoid B and the PCM
    Open in the power supply circuit between the wastegate/boost control solenoid B and the PCM
    Short to ground in the power supply circuit of the wastegate/boost control solenoid B
    Short to power in the power supply circuit of the wastegate/boost control solenoid B
    Wastegate/boost pressure control solenoid B
    Possibly a failed PCM (highly 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, which could save you time and money during diagnosis.

Next, locate the “B” wastegate/boost control solenoid on your specific vehicle. Once located, visually inspect the connectors and wiring. Look for scratches, rubbing, exposed wires, burns, or melted plastic. Separate the connectors and carefully inspect the terminals (the metal parts) inside the connectors. Check if they appear burnt or have a greenish tint indicating corrosion. Use electrical contact cleaner and a plastic bristle brush if terminal cleaning is necessary. Allow it to dry and apply electrical grease where the terminals make contact.

The most common failure is due to electrical/vacuum connection issues.

If you have a scan tool, clear the diagnostic codes from memory and see if P0248 returns. If it doesn’t, the connections were likely your problem.

If the code returns, we will need to test the solenoid and its associated circuits. Typically, there are 2 wires to the wastegate/boost control solenoid. First, disconnect the wiring harness going to the wastegate/boost control solenoid. With a digital multimeter set to ohms (DVOM), connect one lead of the multimeter to one terminal of the solenoid. Connect the remaining multimeter lead to the other terminal of the solenoid. It should not be open or shorted. Check the resistance specifications for your specific vehicle. If the solenoid is open or shorted (infinite resistance or no resistance/0 ohms), replace the solenoid.

If this test passes, use a DVOM to ensure you have 12V at the power supply circuit of the wastegate/boost control solenoid (red lead to the solenoid power circuit, black lead to a good ground). Make sure the ignition is on. If there is no 12 volts at the solenoid, or if there is 12 volts when the ignition is off, repair the wiring from the PCM or relay to the solenoid, or possibly a faulty PCM.

If that checks out, verify that the wastegate/boost control solenoid is properly grounded. Connect a test light to the 12V battery positive (red terminal) and touch the other end of the test light to the ground circuit going to the wastegate/boost control solenoid circuit ground. Using the scan tool to activate the wastegate/boost control solenoid, check if the test light illuminates each time the scan tool activates the solenoid. If the test light does not illuminate, it would indicate a circuit problem. If it does light up, wiggle the wiring harness going to the solenoid to see if the test light flickers, indicating an intermittent connection.

Ensure all mechanical components are secured and functioning properly. Make sure that if vacuum is used, there is sufficient vacuum at the wastegate/boost control solenoid. Otherwise, locate the source of the vacuum blockage or leak.

If all tests have passed so far and you continue to get a P0248 code, it would most likely indicate a faulty wastegate/boost control solenoid, although a defective PCM cannot be ruled out until the solenoid 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.