P0107
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 provides 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 Description
The manifold absolute pressure (MAP) sensor measures the pressure inside the intake manifold. Pressure in the intake manifold is affected by engine speed, throttle opening, 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 sensor translates this action into electrical resistance. The MAP sensor wiring includes 3 circuits. The engine control module (ECM) supplies a regulated 5 volts to the sensor on a 5V 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 highest pressure that can exist in the intake manifold is equal to BARO. This occurs when the vehicle is operated at wide-open throttle (WOT) or when the ignition is ON while the engine is OFF. Under these conditions, the ECM uses the MAP sensor to determine the current BARO. The lowest manifold pressures occur when the vehicle is idling or decelerating. MAP can range from 10 kPa (1.5 psi), when pressures are low, to as much as 104 kPa (15.1 psi), when pressures are high, depending on the BARO. The ECM monitors the MAP sensor signal for pressure outside of the normal range.
Conditions for Running the DTC
P0107 or P0108
* The engine is running.
* These DTCs runs continuously when the above conditions are met.
Conditions for Setting the DTC
P0107
The ECM detects that the MAP sensor voltage is less than 0.2 V for more than 5 s.
P0108
The ECM detects that the MAP sensor voltage is more than 4.5 V for greater than 5 s.
Action Taken When the DTC Sets
DTCs P0107 and P0108 are Type B DTCs.
Conditions for Clearing the MIL/DTC
DTCs P0107 and P0108 are Type B DTCs.
Diagnostic Aids
Verify the integrity of the MAP sensor system by inspecting for the following conditions:
* Intake manifold vacuum leaks
* Any damage to the MAP sensor housing
* Any damage to the MAP sensor seal
* A loose or improperly installed MAP sensor
* A restriction in the vacuum source of the MAP sensor
Reference Information
Schematic Reference
Engine Controls Schematics [1][2]Electrical Diagrams
Connector End View Reference
Component Connector End Views A/C Compressor Clutch
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 Control Module References for scan tool information
Special Tools
J-23738-A - Vacuum Pump
For equivalent regional tools, refer to Special Tools (Diagnostic Tools) Special Tools (Diagnostic Tools).
Circuit/System Verification
* Use the scan tool and compare the MAP Sensor parameter to a known good vehicle, under various operating conditions.
* Use the scan tool and compare the MAP Sensor parameter with ignition ON, with the engine OFF, to the Altitude vs Barometric Pressure table. Refer to Altitude Versus Barometric Pressure Altitude Versus Barometric Pressure.
Circuit/System Testing
1. Ignition OFF, and all vehicle systems OFF, it may take up to 2 minutes for all the systems to power down, disconnect the harness connector at the B74 manifold absolute pressure sensor.
2. Test for less than 2 ohms between the low reference circuit terminal 2 and ground.
• If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the K20 engine control module.
3. Ignition ON, test for 4.8-5.2 V between the 5V reference circuit terminal 1 and ground.
• If less than the specified range, test the 5V reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K20 engine control module.
• If greater than the specified range, test the 5V reference circuit for a short to voltage. If the circuit tests normal, replace the K20 engine control module.
4. Verify the scan tool MAP Sensor parameter is less than 104 kPa (15.1 psi).
• If greater than the specified range, test the signal circuit terminal 3 for a short to voltage. If the circuit tests normal, replace the K20 engine control module.
5. Install a 3A fused jumper wire between the signal circuit terminal 3 and the 5V reference circuit terminal 1. Verify the scan tool MAP Sensor parameter is greater than 103 kPa (14.9 psi).
• If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K20 engine control module.
6. If all circuits test normal, test or replace the B74 manifold absolute pressure sensor.
Component Testing
Note: You must perform the Circuit/System Testing in order to verify the integrity of the MAP sensor circuits before proceeding with the Component Testing.
Skewed Sensor Test
1. Using the following steps and referencing the table below will determine if the B74 manifold absolute pressure sensor is skewed.
2. Ignition ON, engine OFF, observe the MAP sensor scan tool parameter.
3. Use the observed MAP Sensor Scan Tool parameter that is closest to a value that is indicated in the first column.
4. Using the J-23738-A - pump to apply 5 in Hg of vacuum to the MAP sensor, the parameter in the first column should decrease by 17 kPa (2.5 psi). The acceptable range is indicated in the second column.
5. Using the J-23738-A - pump to apply 10 in Hg of vacuum to the MAP sensor, the parameter in the first column should decrease by 34 kPa (5.0 psi). The acceptable range is indicated in the third column.
Erratic Signal Test
1. Ignition OFF, remove the B74 manifold absolute pressure sensor.
2. Install a 3A fused jumper wire between the 5V reference circuit terminal 1 and the corresponding terminal of the B74 manifold absolute pressure sensor.
3. Install a jumper wire between the low reference terminal 2 of the B74 manifold absolute pressure sensor and ground.
4. Install a jumper wire at terminal 3 of the B74 manifold absolute pressure sensor.
5. Connect a DMM between the jumper wire from the terminal 3 of the B74 manifold absolute pressure sensor and ground.
6. Install the J-23738-A - pump to the B74 manifold absolute pressure sensor vacuum port.
7. Ignition ON, slowly apply vacuum to the sensor while observing the DC voltage on the DMM. The voltage should vary between 4.9-0.2 V without any spikes or dropouts.
• If the voltage is erratic, replace the B74 manifold absolute pressure sensor.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.
* Manifold Absolute Pressure Sensor Replacement Service and Repair
* Control Module References Control Module References for ECM replacement, setup, and programming