Fault code P006C is called “MAP – Turbocharger/Supercharger Inlet Pressure 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 P006C
Diagnostic code P006C applies only to vehicles with forced air systems. Other stored Absolute Manifold Pressure (MAP) Sensor or Forced Air Intake System codes must be cleared before this error is corrected.
Atmospheric pressure (air density) is measured either in kilopascals (kPa) or inches of mercury column (Hg) using an absolute pressure sensor in the manifold (MAP). These measurements are fed to the PCM as voltages of varying degrees.
The turbocharger or supercharger inlet pressure sensor is usually of a similar design to the MAP sensor, it also monitors air density. It is most often located inside the turbocharger or supercharger inlet hose.
If the voltage inputs between these sensors differ by more than the programmed degree for a period of time and under certain circumstances. Code P006C will be stored and the Malfunction Indicator Light (MIL) may illuminate.
In some vehicles, it may take several cycles of driving with failure for the MIL indication to appear. The exact specifications for saving the code are described in the documentation of the specific vehicle.
Symptoms of vehicle malfunctions
The main signal that an error P006C has occurred is the Malfunction Indicator Lamp (MIL) is also known as the CheckEngine Light.
It can also be warning signs such as:
- Check engine control lamp on the control panel will light up (the code will be recorded in the memory as a malfunction).
- Decrease of engine power output.
- Rich or poor fuel mixture condition.
- Bad acceleration.
- Increased fuel consumption.
- Unusual noises from turbocharger or pipes during acceleration.
The severity of error P006C may be either minor or serious. Depending on the symptoms and causes of the code.
Factors that can cause this error code
The error code P006C can mean that one or more of the following problems have occurred:
- Faulty or damaged manifold absolute pressure sensor (MAP).
- Faulty pressure sensor at turbocharger or supercharger inlet.
- Damaged or worn connector of one of the sensors.
- Damaged wiring.
- Insufficient vacuum in engine.
- Restricted air supply.
- Sometimes faulty PCM module is the cause.
How to fix or reset OBD-2 code P006C
Some suggested steps for troubleshooting and fix the error code P006C:
- Connect an OBD-II scanner to the vehicle’s diagnostic connector and read all stored data and error codes.
- Clear the error codes from the computer memory and test-drive the vehicle to see if code P006C appears again.
- If the code appears again, check all electrical circuits and associated connectors leading to the MAP and inlet pressure sensors on the turbocharger or supercharger. Make sure they are not broken or worn. Repair or replace if necessary.
- Inspect and test these sensors, and replace if necessary.
- If faulty PCM is the cause, replace or reprogram it.
Diagnose and repair of problems
Inspect visible damage to sensors, wiring, and connectors. Then start the diagnostic procedure with the scan tool. To determine if error P006C is the only error, if not, it may be worth investigating the other trouble codes first.
If no problems with damaged or corroded connectors are found, perform a thorough inspection of all associated wiring. Repair or replace damaged wiring as necessary.
Check the MAP sensor
If the code remains, check the reference voltage at the MAP sensor connector. Also check the ground and continuity, especially in the signal wire between the PCM and the MAP sensor connector. If the resistance is infinite, repair the break in the manifold absolute pressure sensor signal circuit.
If the circuit continuity is normal, check the MAP sensor in operation by connecting a scan tool to the vehicle. The voltage from the MAP sensor should gradually decrease from 5 volts to 1 volt or slightly less, and increase back to about 5 volts. If the signal voltage does not change according to the manufacturer’s specifications, replace the sensor.
Often, MAP sensor readings can get stuck at 4.5 volts, regardless of engine operating conditions. This indicates a short between the signal wire and the 5-volt reference wire. If necessary, repair the wiring to clear the short.
If there is no voltage in the signal wire when the MAP sensor connector is disconnected, there is an internal short and the sensor must be replaced.
The test procedure for a turbocharger or supercharger inlet pressure sensor will be similar. Also in some cases the PCM may be faulty or in the process of breaking down. But this is extremely rare. Therefore, before replacing it, it’s better to check everything thoroughly again.
On which vehicles does this problem occur most frequently
Fault code P006C can occur on different vehicles but there are statistics on which brands this occurs most often. Here is a list of some of them:
- BMW
- Chevrolet (Traverse)
- Chrysler
- Dodge (Sprinter)
- Fiat
- Ford
- Land Rover (Range Rover)
- Mazda
- Mercedes-Benz (Sprinter)
- Toyota
- Volkswagen (Vento)
Fault code P006C can sometimes be found with other errors. The most common are the following: P0068, P0069, P006A, P006B, P006D.
