Technical Description of OBD-II Trouble Code
Correlation between MAP – Turbocharger/Supercharger Inlet Pressure
What does that signify?
This generic powertrain diagnostic trouble code (DTC) is commonly found in many OBD-II vehicles, including Toyota, Dodge, Chrysler, Fiat, Sprinter, VW, Mazda, and others.
A stored code P006C indicates that the powertrain control module (PCM) has detected a discrepancy in the signals between the manifold absolute pressure (MAP) sensor and the turbocharger/supercharger inlet pressure sensor.
In certain vehicle applications, the MAP sensor may be referred to as a barometric pressure sensor. The code P006C is only applicable to vehicles with forced air induction systems.
Before diagnosing a code P006C, it is important to address any other stored MAP sensor or forced air induction system codes.
The MAP sensor measures intake manifold absolute pressure (air density) in kilopascal (kPa) or inches of mercury (Hg) units. These measurements are converted into varying degrees of voltage and input to the PCM. MAP and barometric pressure signals are measured in similar increments.
The turbocharger/supercharger inlet pressure sensor is similar in design to the MAP sensor and also monitors air density. It is usually located inside the turbocharger/supercharger inlet hose and provides the PCM with a voltage signal reflecting the air density.
If the voltage input signals between the MAP sensor and the turbocharger/supercharger inlet pressure sensor differ by more than a programmed degree over a certain period of time and under specific circumstances, a code P006C will be stored and the malfunction indicator lamp (MIL) may illuminate.
In some cases, MIL illumination may require multiple drive cycles with a failure. For exact code storage parameters, consult a reliable vehicle information source such as AllData DIY.
What is the severity of this DTC?
The conditions leading to the storage of a code P006C can hinder engine performance, drivability, and fuel efficiency. It should be addressed urgently.
What are some of the symptoms of the code?
Symptoms of a P006C engine code may include:
What are some of the common causes of the code?
Possible causes for this engine code may include:
What are some P006C troubleshooting steps?
To begin troubleshooting a code P006C, visually inspect all MAP sensor and turbocharger inlet pressure sensor wiring and connectors. Ensure that the turbocharger/supercharger inlet hoses are secure and in good condition. Inspect the air filter for cleanliness and obstruction.
When diagnosing a code P006C, you will need a manual vacuum pressure gauge, a diagnostic scanner, a digital volt/ohmmeter (DVOM), and a reliable source of vehicle information.
A manual engine intake vacuum pressure test is a recommended precursor to any MAP related code. Use a vacuum pressure gauge and refer to your vehicle information source for specification guidelines. If engine vacuum is insufficient, there may be an internal engine malfunction that needs to be addressed before proceeding.
Next, connect the scanner to the vehicle diagnostic port and retrieve all stored codes and freeze frame data. Freeze frame data provides information about the circumstances at the moment of the malfunction that led to the stored code P006C. Take note of this information as it may be helpful during the diagnosis. Clear the codes and test-drive the vehicle to see if the code is reset.
If the code is reset:
If the appropriate reference voltage and ground are present:
If the respective sensors are within manufacturer’s specifications:
If the correct MAP sensor and turbocharger/supercharger inlet pressure sensor voltage signal is present:
If all MAP/turbocharger/supercharger inlet pressure sensors and circuits are within specifications, suspect PCM failure or a PCM programming error.
