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VIN 6




DTC P0107 or P0108

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Strategy Based Diagnosis) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Diagnostic Procedure Instructions) provide an overview of each diagnostic category.

DTC Descriptors
DTC P0107
- Manifold Absolute Pressure (MAP) Sensor Circuit Low Voltage

DTC P0108
- Manifold Absolute Pressure (MAP) Sensor Circuit High Voltage

Diagnostic Fault Information





Typical Scan Tool Data





Circuit/System Description

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, air temperature, and barometric pressure (BARO). A diaphragm within the MAP sensor is displaced by the pressure changes that occur from the varying load and operating conditions of the engine. The engine control module (ECM) supplies a regulated 5 volts to the sensor on a 5-volt reference circuit. The ECM supplies a ground on a low reference circuit. The MAP sensor provides a signal voltage to the ECM, relative to the pressure changes, 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 BARO. This occurs when the vehicle is operating at idle or when the ignition is ON, while the engine is OFF. The ECM uses the MAP sensor to aid in diagnosis of the turbocharger performance. 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 greater than 240 kPa (34 psi) when pressures are high, depending on the BARO.

Conditions for Running the DTC

* The engine is running for more than 1 second.
* The engine speed is between 500-2,500 RPM.
* The ignition 1 voltage is more than 11 volts.
* The above conditions are met for more than 2 seconds.
* DTC P0107 and P0108 run continuously when the above enabling conditions are met.

Conditions for Setting the DTC

P0107

The ECM detects that the MAP sensor pressure is less than 10 kPa for 10 seconds.

P0108

The ECM detects that the MAP sensor pressure is greater than 306 kPa for greater than 2 seconds.

Action Taken When the DTC Sets

* DTCs P0107 and P0108 are Type A DTCs.
* DPF Regeneration is inhibited.
* The ECM commands Reduced Engine Power mode.
* A message center or an indicator may display Reduced Engine Power.

Conditions for Clearing the DTC

DTCs P0107 and P0108 are Type A DTCs.

Diagnostic Aids

* A wide open throttle (WOT) acceleration from a stop should cause the MAP sensor parameter on the scan tool to increase rapidly.
* Verify that any electrical aftermarket devices are properly connected and grounded. Refer to Checking Aftermarket Accessories (Checking Aftermarket Accessories).

Reference Information
Schematic Reference

Engine Controls Schematics ([1][2]Electrical Diagrams)
Connector End View Reference

Component Connector End Views (Connector End Views By Name)
Electrical Information Reference

* Circuit Testing (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions (Powertrain Diagnostic Trouble Code (DTC) Type Definitions)
Scan Tool Reference

Control Module References (Programming and Relearning) for scan tool information
Special Tools

* J-23738-A Mityvac
* J-35555 Metal Mityvac

Circuit/System Verification

1. Verify that DTCs P003A, P0047, P0048, P0234, P0698, P0699, or P2563 are not set.

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

2. Determine the current vehicle testing altitude. Ignition ON, observe the scan tool BARO Sensor parameter. Compare the parameter to the Altitude vs. Barometric Pressure table. Refer to Altitude Versus Barometric Pressure (Altitude Versus Barometric Pressure).
3. Ignition ON, engine OFF, observe the scan tool MAP Sensor parameter. The MAP Sensor parameters should match the BARO Sensor parameter.
4. Engine running, observe the scan tool MAP Sensor parameter. Slowly increase the engine speed to 2,000 RPM, then allow the engine speed to return to a stable idle. The MAP Sensor parameter should increment to a higher value at 2,000 RPM and return to near BARO at idle speed.
5. 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.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the MAP sensor.
2. Ignition OFF and scan tool disconnected for 90 seconds, test for less than 5 ohms between the low reference circuit terminal A and a good ground.

• If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the ECM.

3. Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal C and ground.

• If less than the specified range, test the 5-volt reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the ECM.

• If greater than the specified range, test the 5 volt reference circuit for a short to voltage. If the circuit tests normal, replace the ECM.

4. Verify the scan tool MAP Sensor parameter is less than 45 kPa.

• If greater than the specified range, test the signal circuit terminal B for a short to voltage. If the circuit tests normal, replace the ECM.

5. Install a 3A fused jumper wire between the signal circuit terminal B and the 5-volt reference circuit terminal C. Verify the scan tool MAP Sensor parameter is greater than 250 kPa.

• If less than the specified range, test the sensor signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the ECM.

6. If all circuits test normal, test or replace the MAP sensor.

Component Testing

Important: You must perform the Circuit/System Testing in order to verify the integrity of the MAP sensor circuits before proceeding with the Component Testing.


Erratic Signal Test
1. Ignition OFF, disconnect and remove the MAP sensor.
2. Install a 3A fused jumper wire between the 5-volt reference circuit terminal C and the corresponding terminal C of the MAP sensor.
3. Install a jumper wire between the low reference terminal A of the MAP sensor and ground.
4. Install a jumper wire at the signal terminal B of the MAP sensor.
5. Connect a DMM between the jumper wire from terminal B of the MAP sensor and ground.
6. Ignition ON, install the J-35555 or J-23738-A to the MAP sensor port. Slowly apply vacuum to the sensor while monitoring the voltage on the DMM. The voltage should vary between 4.9-0.02 volts, without any spikes or dropouts.

• If the voltage is erratic, replace the MAP sensor.

Repair Instructions

* Manifold Absolute Pressure Sensor Replacement (Service and Repair)
* Control Module References (Programming and Relearning) for ECM replacement, setup, and programming

Repair Verification

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 90 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 Diagnostic Trouble Code (DTC) List - Vehicle (Diagnostic Trouble Code (DTC) List - Vehicle) and perform the appropriate diagnostic procedure.
6. Engine running, observe the scan tool Soot Mass parameter. The value should be less than 30 grams.

• If the Soot Mass value is greater than 30 grams, perform the Diesel Particulate Filter (DPF) Regeneration Enable (Diesel Particulate Filter (DPF) Regeneration Enable)

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