Circuit Description
The manifold absolute pressure (MAP) sensor responds to pressure changes in the intake manifold. The pressure changes occur based on the engine load. The MAP sensor has the following circuits:
| • | 5-volt reference circuit |
| • | Low reference circuit |
| • | MAP sensor signal circuit |
The engine control module (ECM) supplies 5 volts to the MAP sensor on the 5-volt reference circuit. The ECM also provides a ground on the low reference circuit. The MAP sensor provides a signal to the ECM on the MAP sensor signal circuit which is relative to the pressure changes in the manifold. The ECM should detect a low signal voltage at a low MAP, such as during an idle or a deceleration. The ECM should detect a high signal voltage at a high MAP, such as the ignition is ON, with the engine OFF, or at a wide open throttle (WOT). The MAP sensor is also used in order to determine the barometric pressure (BARO). This occurs when the ignition switch is turned ON, with the engine OFF. The BARO reading may also be updated whenever the engine is operated at WOT. The ECM monitors the MAP sensor signal for voltage outside of the normal range.
If the ECM detects a MAP sensor signal voltage that is excessively low, DTC P0107 sets.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC P0107 Manifold Absolute Pressure (MAP) Sensor Circuit Low Voltage
Conditions for Running the DTC
| • | DTCs P0120, P0121, P0122, P0123, P0220, P0222, P0223, P0641, P0651, P1515, P1516, P2101, P2119, P2135, P2176 are not set. |
| • | The engine is running. |
| • | The throttle angle is more than 0 percent when the engine speed is less than 800 RPM. |
| OR |
| • | The throttle angle is more than 12.5 percent when the engine speed is more than 800 RPM. |
| • | The above conditions are present for 4 seconds. |
| • | DTC P0107 runs continuously when the above conditions are met. |
Conditions for Setting the DTC
The ECM detects that the MAP sensor voltage is less than 0.06 volt for more than 3.2 seconds.
Action Taken When the DTC Sets
| • | The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails. |
| • | The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records. |
Conditions for Clearing the MIL/DTC
| • | The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail. |
| • | A current DTC, Last Test Failed, clears when the diagnostic runs and passes. |
| • | A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic. |
| • | Clear the MIL and the DTC with a scan tool. |
Test Description
The number below refers to the step number on the diagnostic table.
Step | Action | Values | Yes | No |
|---|---|---|---|---|
Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Control Module Connector End Views or Engine Controls Connector End Views | ||||
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | |
2 |
Is DTC P0641 also set? | -- | Go to DTC P0641 | Go to Step 3 |
3 | Observe the manifold absolute pressure (MAP) sensor parameter with the scan tool. Is the voltage less than the specified value? | 0.1 V | Go to Step 5 | Go to Step 4 |
Did the DTC fail this ignition? | -- | Go to Step 5 | Go to Testing for Intermittent Conditions and Poor Connections | |
5 |
Important: Certain resistances will not be detectable if a test lamp is not connected to provide a circuit load. Is the voltage more than the specified value? | 4.8 V | Go to Step 6 | Go to Step 7 |
6 |
Is the voltage more than the specified value? | 4.9 V | Go to Step 9 | Go to Step 8 |
7 | Test the 5-volt reference circuit between the engine control module (ECM) and the MAP sensor for an open or high resistance. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | -- | Go to Step 13 | Go to Step 10 |
8 | Test the MAP sensor signal circuit between the ECM and the MAP sensor for a short to ground or an open. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | -- | Go to Step 13 | Go to Step 10 |
9 | Test for an intermittent and for a poor connection at the MAP sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | -- | Go to Step 13 | Go to Step 11 |
10 | Test for an intermittent and for a poor connection at the ECM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | -- | Go to Step 13 | Go to Step 12 |
11 | Replace the MAP sensor. Refer to Manifold Absolute Pressure Sensor Replacement . Did you complete the replacement? | -- | Go to Step 13 | -- |
12 | Replace the ECM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement? | -- | Go to Step 13 | -- |
13 |
Did the DTC fail this ignition? | -- | Go to Step 2 | Go to Step 14 |
14 | Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed? | -- | System OK | |
