Circuit Description
The manifold absolute pressure (MAP) sensor responds to changes in intake manifold pressure. The MAP sensor signal voltage to the powertrain control module (PCM) varies from less than 2 volts at idle, high vacuum, to more than 4 volts with the key ON, engine not running, or at wide-open throttle, low vacuum. The MAP sensor is used to determine manifold pressure changes while the EGR flow test diagnostic is being run, and to update the barometric pressure reading (BARO), as an enabling factor for other diagnostics. Refer to DTC P0401 Exhaust Gas Recirculation (EGR) Flow Insufficient . The PCM monitors the MAP signals for voltages outside the normal range of the MAP sensor. If the PCM detects a MAP sensor signal voltage that is excessively low, DTC P0107 will set.
Conditions for Running the DTC
| • | TP sensor DTCs are not present. |
| • | The system voltage is more than 9 volts. |
| • | The engine is running. |
| • | The throttle angle is above 0 percent, if the engine speed is less than 1000 RPM. |
| • | The throttle angle is above 10 percent, if the engine speed is more than 1000 RPM. |
Conditions for Setting the DTC
| • | The MAP sensor signal voltage is less than 0.1 volt (12 kPa). |
| • | The above conditions are present for longer than 200 3X reference periods, or 67 crankshaft revolutions. |
Action Taken When the DTC Sets
| • | The PCM will illuminate the malfunction indicator lamp (MIL) during the second consecutive trip in which the diagnostic test has been run and failed. |
| • | The PCM will store conditions which were present when the DTC set as Freeze Frame/Failure Records data. |
Conditions for Clearing the MIL/DTC
| • | The PCM will turn OFF the malfunction indicator lamp (MIL) during the third consecutive trip in which the diagnostic has run and passed. |
| • | The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction. |
| • | The DTC can be cleared by using a scan tool. |
Diagnostic Aids
Inspect for a misrouted harness-- Inspect the MAF sensor harness to ensure that it is not routed too close to high voltage wires such as spark plug leads.
Many situations may lead to an intermittent condition. Perform each inspection or test as directed.
Important: : Remove any debris from the connector surfaces before servicing a component. Inspect the connector gaskets when diagnosing or replacing a component. Ensure that the gaskets are installed correctly. The gaskets prevent contaminate intrusion.
| • | Loose terminal connection |
| - | Use a corresponding mating terminal to test for proper tension. Refer to Testing for Intermittent Conditions and Poor Connections , and to Connector Repairs in Wiring Systems for diagnosis and repair. |
| - | Inspect the harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, and faulty terminal to wire connection. Refer to Testing for Intermittent Conditions and Poor Connections , and to Connector Repairs in Wiring Systems for diagnosis and repair. |
| • | Damaged harness--Inspect the wiring harness for damage. If the harness inspection does not reveal a problem, observe the display on the scan tool while moving connectors and wiring harnesses related to the sensor. A change in the scan tool display may indicate the location of the fault. Refer to Wiring Repairs in Wiring Systems for diagnosis and repair. |
| • | Inspect the powertrain control module (PCM) and the engine grounds for clean and secure connections. Refer to Wiring Repairs in Wiring Systems for diagnosis and repair. |
If the condition is determined to be intermittent, reviewing the Snapshot or Freeze Frame/Failure Records may be useful in determining when the DTC or condition was identified.
Test Description
The numbers below refer to the step numbers on the diagnostic table.
Step | Action | Values | Yes | No |
|---|---|---|---|---|
1 | Did you perform the Powertrain On Board Diagnostic (OBD) System Check? | -- | ||
2 |
Important: If DTC P1635 is set refer to DTC P1635 5 Volt Reference Circuit first.
Does the MAP voltage measure less then the specified value? | 0.1V | ||
3 |
Does the scan tool indicate DTC P0107 failed? | -- | Go to Diagnostic Aids | |
4 |
Does the MAP voltage measure near the specified value? | 4.95V | ||
5 |
Does the MAP voltage measure near the specified value? | 4.95V | ||
6 |
Did you find and correct the condition? | -- | ||
7 |
Did you find and correct the condition? | -- | ||
8 |
Did you find and correct the condition? | -- | ||
9 |
Did you find and correct the condition? | -- | ||
10 |
Did you find and correct the condition? | -- | ||
11 | Replace the MAP sensor. Refer to Manifold Absolute Pressure Sensor Replacement . Did you complete the replacement? | -- | -- | |
|
Important: The replacement PCM must be programmed. Replace the PCM. Refer to Powertrain Control Module Replacement/Programming . Did you complete the replacement? | -- | -- | ||
13 |
Does the DTC reset? | -- | System OK |
