Trouble code solution P023D: decoding, causes, resetting, meaning

Contents

Technical description and explained code P023D
Symptoms of vehicle malfunctions
Factors that can cause this error code
How to fix or reset OBD-2 code P023D
Diagnose and repair of problems
Checking the vacuum
Measuring boost pressure, turbocharger inspection
Solenoid and wiring
On which vehicles does this problem occur most frequently
Video

Fault code P023D is called “Manifold Absolute Pressure – Turbocharger/Supercharger Boost Sensor “A” Correlation” but in different programs it may be called differently. This fault designation applies to all vehicles equipped with OBD-II.

Technical description and explained code P023D

Stored code P023D means that the Powertrain Control Module (PCM) has detected a mismatch in the correlated signals. Between the Absolute Manifold Pressure (MAP) sensor and the turbocharger/charger boost sensor marked “A”.

The letter “A” denotes a specific boost sensor in a system that may use multiple boost sensors in different locations. This code only applies to vehicles equipped with forced air devices. Forced air devices include turbochargers and superchargers.

The MAP sensor provides a voltage signal to the PCM that reflects the air density or pressure in the intake manifold. The voltage signal is received (by the PCM) either in kilopascals (kPa) or inches of mercury (Hg).

The turbocharger/charger boost pressure sensor is likely to have a similar design to the MAP sensor. It monitors the air density inside the turbocharger intake tube and gives the PCM a corresponding voltage signal.

Code P023D will be stored and the malfunction indicator lamp (MIL) may illuminate. If the PCM detects voltage signals between the MAP sensor and boost “A” sensor. Which are different from the programmed reference value.

It may take several failure cycles for the MIL check lamp to illuminate on the instrument cluster.

Symptoms of vehicle malfunctions

The main signal that an error P023D has occurred is the Malfunction Indicator Lamp (MIL) is also known as the CheckEngine Light.

It can also be warning signs such as:

The “Check engine” control lamp on the control panel will light up (the code will be stored as a fault).
Other related fault codes may also be present.
Loss of power may be observed.
Rich or depleted exhaust.
Poor engine starting, especially when cold.
Increased fuel consumption.

The severity of fault code P023D is medium, but overall engine performance may be affected. And fuel economy may be adversely affected by conditions that contribute to the occurrence of the code.

Factors that can cause this error code

The error code P023D can mean that one or more of the following problems have occurred:

Faulty manifold absolute pressure sensor (MAP).
Failed turbocharger boost sensor.
Damaged, burned, shorted, disconnected, corroded wires or connectors.
Short circuit or break in wiring harness between sensors and PCM.
Turbocharger problem.
Sometimes faulty PCM module or PCM programming error is the cause.

How to fix or reset OBD-2 code P023D

Some suggested steps for troubleshooting and fix the error code P023D:

Read all stored data and error codes with an OBD-II scan tool.
Clear the error codes from the computer memory and test-drive the vehicle to find out if error P023D appears again.
Check the operation of the absolute manifold pressure (MAP) sensor.
Inspect the turbocharger boost pressure sensor.
Test the connector and wiring for damage, looseness, and corrosion.
Check the PCM module.

Diagnose and repair of problems

Turbines typically spin at incredible speeds of 100,000 to 150,000 rpm. They are intolerant to imbalance or a lack of clean oil in the bearing.

The diagnostic process for the P023D error is best started with the most common turbo problems. These will require tools such as a vacuum gauge and a dial gauge.

Checking the vacuum

Make sure the engine is running properly, with no ignition skips or codes related to a faulty detonation sensor. Then, check for leaks at the turbocharger outlet, intercooler, and throttle body.

Inspect the intake manifold for leaks of any kind, including vacuum hoses. Remove the lever from the throttle valve. Manually operate the valve, looking for a jammed valve causing a drop in boost.

Measuring boost pressure, turbocharger inspection

Locate the vacuum with no holes in the intake manifold and install a vacuum gauge. Start the engine. At idle the engine should have a vacuum of 1-1.5 atmospheres. If less than 1 atmosphere then the catalytic converter is defective and will not allow boost.

Quickly accelerate the engine to 5000 rpm and release the throttle, observing the vacuum gauge indicating the boost pressure. If the boost pressure rises above 1.3 atmospheres, then the bypass valve is bad.

Stop the engine and let it cool down. Remove the turbine exhaust hose and look inside to make sure the blades are not rubbing the housing. Look for bent or missing blades or oil in the turbocharger. Rotate the blades by hand, looking for resistance indicating turbocharger malfunction.

Inspect the oil lines from the cylinder block to the center bearing and the return line from the bearing to the oil pan for leaks. Place a dial gauge on the turbine outlet and rotate the turbine shaft. If the axial play exceeds 0.003, the center bearing is defective.

Solenoid and wiring

If after all the checks no problems are found, but code P023D has not disappeared, it is necessary to check the electrical components. You need to test the sensors and associated circuits.

Disconnect the wiring harness and test the control circuit. Make sure that 12 volts are present in the power circuit. They should show when the ignition is on. If they are not, or if they are present when the ignition is off, repair the wiring from the PCM to the sensor.

Check that the valves are securely grounded. Connect the test lamp to the plus side of the battery, and touch the other end to the valve ground circuit. If the pilot light does not come on, it indicates a faulty circuit.