The manifold absolute pressure (MAP) sensor measures the pressure inside the intake manifold. Pressure in the intake manifold is affected by turbocharger output, engine speed, accelerator pedal input, ambient air temperature, and barometric pressure (BARO). A diaphragm within the MAP pressure sensor is displaced by the pressure changes that occur from the varying load and operating conditions of the engine. The sensor translates these changes into electrical resistance. The engine control module (ECM) supplies a regulated 5 volts on the 5-volt reference circuit and a ground on a low reference circuit. The MAP sensor provides a signal voltage to the ECM, relative to intake manifold pressures, on the MAP sensor signal circuit. The ECM converts the signal voltage input to a pressure value. Under normal operation, the lowest pressure that can exist in the intake manifold is equal to the BARO. This occurs when the vehicle is operated at idle or when the ignition is ON while the engine is OFF. The highest manifold pressures occur when the turbocharger output is high. Manifold pressure can range from 58 kPa (8 psi) when pressures are low to more than 295 kPa (42.7 psi) when pressures are high, depending on the BARO. The MAP pressure sensor has a range of 43-365 kPa (6-53 psi). The ECM monitors the MAP sensor by comparing a calculated predicted value at a predetermined engine load and speed, to the actual sensor input.

The measured MAP pressure is more than 39 kPa below the expected range for 10 seconds.

DTC P0299 is a Type A DTC.

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Electrical Information Reference

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

1. Verify that DTCs P003A, P0047, P0048, P046C, P0402, P0403, P0698, P0699, P2563, P2564 or P2565 are not set.

⇒	If any of the DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle.

2. Engine running, command the TC Vane Pos. Ctrl. Solenoid ON, while performing a snapshot of the induction data list. Perform the following actions during the snapshot: Refer to Scan Tool Snapshot Procedure.

2.1.	Slowly increase the engine speed to 1,700 RPM for 5 seconds and then return the engine speed to idle.

2.2.	Plot the snapshot and verify that the MAP sensor parameter increases smoothly and follows the Engine Speed parameter as the engine speed is increased, and then returned to idle.

⇒	If the MAP parameter plot slope is not a straight line with even the RPM change, replace the MAP sensor.

3. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Important: Perform the Repair Verification after completing the Circuit/System Testing.

1. Verify the integrity of the air induction system, the turbocharger ducts and hoses by inspecting for the following conditions:

•	Any damaged components

•	Any loose or improperly installed components

•	A wet or restricted air filter

•	Any exhaust leaks before the turbocharger

•	Any exhaust restrictions after the turbocharger

•	Any snow or ice build-up in cold climates at the air cleaner and MAF sensor

•	Any water, snow, ice build-up, restrictions or coking at the MAP sensor

2. Test the charge air cooler for leaks. Refer to Charge Air Cooler Diagnosis.
3. Test the turbocharger oil supply feed. Refer to Turbocharger Lack of Oil Supply.
4. Inspect the turbocharger oil supply tube for restrictions.

⇒	If a restriction is found, clean or replace the oil supply tube as necessary.

5. Inspect the turbocharger for debris, worn impeller and turbine blades, or damage Refer to Turbocharger Cleaning and Inspection.

⇒	If worn or damaged turbocharger blades or vanes are found, replace the turbocharger assembly.

6. If the induction system, charger air cooler system, the turbocharger, and the turbocharger oil supply test normal, replace the MAP sensor.

1. Install any components or connectors that have been removed or replaced during diagnosis.
2. Perform any adjustment, programming, or setup procedures that are required when a component or module is removed or replaced.
3. Clear the DTCs.
4. Turn OFF the ignition for 60 seconds.
5. Duplicate the Conditions for Running the DTC and use the freeze Frame/Failure Records, if applicable, in order to verify the DTC does not reset. If the DTC resets or another DTC is present, refer to the Diagnostic Trouble Code (DTC) List - Vehicle and perform the appropriate diagnostic procedure.
6. Engine running, command the TC Vane Pos. Ctrl. Solenoid ON while performing a snapshot of the induction data list. Perform the following actions during the snapshot: Refer to Scan Tool Snapshot Procedure.

⇒	Slowly increase the engine speed to 1,700 RPM for 5 seconds, then return the engine speed to idle.

⇒	Plot the snapshot and verify that the MAP sensor parameter increases smoothly and follows the Engine Speed parameter as the engine speed is increased, then returned to idle.

7. If any service has been performed on the turbocharger or on the turbocharger components, a turbocharger relearn must be performed. Failure to perform the turbocharger learn procedure may cause this DTC to set. Refer to Turbocharger Learn.
8. Perform the Diesel Particulate Filter (DPF) Service Regeneration.