P2564 Turbocharger Boost Control Position Sensor Circuit Low

P2564 is a generic OBD-II diagnostic trouble code that indicates the Engine Control Module (ECM) has detected a low voltage condition in the Turbocharger Boost Control Position Sensor Circuit.

In simple terms, the ECM is receiving a voltage signal from the turbocharger boost control position sensor that is lower than the manufacturer's expected range. As a result, the ECM cannot accurately determine the position of the turbocharger actuator or the variable geometry mechanism, which can affect boost pressure control and engine performance.

The Turbocharger Boost Control Position Sensor continuously monitors the position of the turbocharger actuator and provides feedback to the ECM. This information allows the engine computer to regulate turbo boost efficiently under different driving conditions.

When the ECM detects a low voltage signal from this sensor circuit, it stores diagnostic trouble code P2564 and may illuminate the Check Engine Light.

What Does P2564 Mean?

Turbocharged engines use either a Variable Geometry Turbocharger (VGT) or a wastegate actuator to control boost pressure.

The Turbocharger Boost Control Position Sensor monitors the movement of the actuator and reports its position to the ECM.

The turbocharger control system typically includes:

• Turbocharger

• Turbocharger Boost Control Position Sensor

• Turbocharger actuator

• Variable Geometry Turbocharger (VGT) vanes or wastegate

• Boost control solenoid (on some models)

• Engine Control Module (ECM)

The ECM uses this information to:

• Monitor actuator position

• Regulate boost pressure

• Prevent overboost and underboost

• Improve fuel efficiency

• Reduce emissions

• Protect the turbocharger from damage

The code description contains several important meanings:

Turbocharger Boost Control Position Sensor

This sensor measures the position of the turbocharger actuator or VGT mechanism.

Circuit

The circuit includes:

• 5-volt reference supply

• Ground circuit

• Signal wire

• Electrical connectors

• ECM communication

Low

The ECM detects a signal voltage below the expected operating range.

Possible causes include:

• Short to ground

• Faulty sensor

• Open reference voltage circuit

• Damaged wiring

• Poor electrical connections

Symptoms of P2564

The symptoms of P2564 may vary depending on how much the turbocharger control system is affected.

Common symptoms include:

Check Engine Light

The Check Engine Light usually turns on after the ECM detects the low sensor signal.

Reduced engine power

The ECM may reduce turbocharger operation to protect the engine.

Possible symptoms include:

• Weak acceleration

• Poor throttle response

• Reduced engine performance

Limp mode

Many vehicles activate a reduced-power mode when accurate boost control is no longer possible.

Turbocharger boost problems

The turbocharger may produce:

• Low boost pressure

• Delayed boost response

• Inconsistent boost levels

Engine hesitation

The vehicle may hesitate during acceleration because the ECM cannot correctly control boost pressure.

Poor fuel economy

Incorrect boost control can reduce engine efficiency and increase fuel consumption.

Excessive exhaust smoke (diesel engines)

Diesel engines may produce black smoke due to incomplete combustion caused by insufficient boost pressure.

Common Causes of P2564

Several problems can cause a Turbocharger Boost Control Position Sensor Circuit Low condition.

Faulty Turbocharger Boost Control Position Sensor

A failing position sensor is one of the most common causes.

Possible failures include:

• Internal electrical failure

• Low signal output

• Heat damage

• Internal circuit defects

Short to ground

The sensor signal wire may contact the vehicle chassis or another ground source.

Possible causes include:

• Damaged insulation

• Chafed wiring

• Melted wires near the turbocharger

Open reference voltage circuit

If the ECM cannot supply the required reference voltage, the sensor signal may remain low.

Possible causes include:

• Broken reference wire

• Loose connector

• Damaged ECM wiring

Damaged wiring harness

The wiring near the turbocharger operates in a high-temperature environment.

Possible wiring problems include:

• Broken wires

• Heat damage

• High resistance

• Vibration-related wear

Corroded or loose connectors

Poor electrical connections may reduce signal voltage.

Possible connector problems include:

• Corrosion

• Loose terminals

• Bent pins

• Moisture intrusion

Faulty turbocharger actuator

A malfunctioning actuator may prevent the sensor from accurately reporting position.

Possible causes include:

• Mechanical wear

• Internal electrical failure

• Actuator binding

Variable Geometry Turbocharger (VGT) problems

Carbon buildup can restrict vane movement and affect position feedback.

Possible causes include:

• Carbon deposits

• Rust

• Mechanical sticking

ECM problems

Although uncommon, the ECM may fail to process the sensor signal correctly.

Possible causes include:

• Internal ECM failure

• Software issues

• Damaged ECM connector

Vehicles Commonly Affected by P2564

P2564 may occur on many turbocharged gasoline and diesel engines equipped with electronic boost control systems.

Common examples include:

• Ford Power Stroke diesel engines

• Chevrolet Duramax diesel engines

• GMC diesel trucks

• Dodge Ram Cummins diesel engines

• Volkswagen TDI models

• Audi TDI vehicles

• BMW turbocharged diesel engines

• Mercedes-Benz CDI diesel models

• Jeep EcoDiesel vehicles

The exact repair procedure depends on the vehicle manufacturer and turbocharger design.

How Is P2564 Diagnosed?

Proper diagnosis requires checking both the electrical circuit and the turbocharger control system.

Check for additional trouble codes

A professional scan tool should check for related codes such as:

• Turbocharger actuator codes

• Boost pressure sensor codes

• MAP sensor codes

• Underboost or overboost codes

Related diagnostic codes can help identify the root cause.

Inspect the sensor

The Turbocharger Boost Control Position Sensor should be inspected for:

• Physical damage

• Oil contamination

• Proper mounting

• Connector condition

Inspect wiring and connectors

Technicians should inspect the entire circuit for:

• Broken wires

• Short-to-ground conditions

• Heat damage

• Corrosion

• Loose terminals

Monitor live sensor data

A diagnostic scan tool should monitor:

• Requested actuator position

• Actual actuator position

• Sensor voltage

• Boost pressure

The sensor values should change smoothly as engine load changes.

Test the turbocharger actuator

The actuator should be checked for:

• Smooth movement

• Full operating range

• Proper electrical or vacuum response

Inspect the turbocharger

Technicians should inspect:

• Variable geometry vanes

• Wastegate operation

• Carbon buildup

• Mechanical binding

How to Fix P2564

The appropriate repair depends on the cause of the low voltage condition.

Common repairs include:

Replacing the Turbocharger Boost Control Position Sensor

If the sensor has failed internally, replacement is usually required.

Repairing damaged wiring

Electrical repairs may include:

• Replacing damaged wires

• Repairing short-to-ground faults

• Restoring damaged insulation

Repairing connector problems

Repairs may include:

• Cleaning corroded terminals

• Replacing damaged connectors

• Securing loose electrical connections

Repairing the reference voltage circuit

Broken or damaged reference voltage wiring should be repaired.

Replacing the turbocharger actuator

A faulty actuator should be replaced if it cannot accurately control boost pressure.

Cleaning the Variable Geometry Turbocharger

Removing carbon buildup may restore smooth vane movement.

Repairing ECM-related faults

In rare cases, ECM programming updates or replacement may be necessary.

After repairs:

1. Clear the diagnostic trouble code.

2. Start the engine.

3. Monitor live sensor data.

4. Perform a road test.

5. Confirm that the code does not return.

Can You Drive With P2564?

Driving with P2564 may be possible for a short time, but it is not recommended.

Possible risks include:

• Reduced engine performance

• Loss of turbocharger efficiency

• Limp mode activation

• Increased fuel consumption

• Higher exhaust emissions

If the vehicle experiences severe power loss or repeatedly enters limp mode, it should be inspected as soon as possible.

Is P2564 a Serious Code?

P2564 is generally considered a moderate to serious diagnostic trouble code.

Although the vehicle may still be drivable, incorrect turbocharger position feedback can result in:

• Poor engine performance

• Reduced fuel economy

• Improper boost pressure control

• Increased emissions

• Additional turbocharger wear

Prompt diagnosis helps prevent more serious turbocharger or engine management problems.

How to Prevent P2564

Routine maintenance can reduce the risk of turbocharger control system failures.

Recommended practices include:

• Inspect turbocharger wiring regularly.

• Keep electrical connectors clean and dry.

• Repair damaged wiring immediately.

• Replace worn vacuum hoses where applicable.

• Use the correct engine oil recommended by the manufacturer.

• Follow scheduled maintenance intervals.

• Investigate Check Engine Light warnings without delay.

Final Thoughts

P2564 Turbocharger Boost Control Position Sensor Circuit Low indicates that the ECM has detected a voltage signal from the turbocharger boost control position sensor that is below the expected operating range.

The most common causes include a faulty position sensor, short-to-ground wiring faults, damaged connectors, reference voltage problems, a defective turbocharger actuator, sticking variable geometry vanes, or, in rare cases, an ECM malfunction.

A complete inspection of the sensor, electrical circuit, actuator, and turbocharger assembly is essential to restore proper boost control, maintain engine performance, improve fuel efficiency, and ensure reliable long-term operation.