Circuit Description
The manifold absolute pressure (MAP) sensor responds to changes in intake manifold pressure (vacuum). The MAP sensor signal voltage to the PCM varies from below 2 volts at idle (high vacuum) to above 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, refer to DTC P0401 Exhaust Gas Recirculation (EGR) Flow Insufficient . Also to update the barometric pressure reading (BARO), as an enabling factor for other diagnostics. 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
| • | No TP sensor DTCs present |
| • | System voltage more than 9 volts |
| • | The engine is running. |
| • | Idle speed is steady. |
| • | Throttle angle above 0 percent, if engine speed is less than 1000 RPM. |
| • | Throttle angle above 10 percent, if engine speed is more than 1000 RPM. |
Conditions for Setting the DTC
| • | The MAP sensor signal voltage is less than 0.1 volt. |
| • | Above conditions are present for more than 200 3X reference periods (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
Check for the following conditions:
| • | Poor connection at the PCM -- Inspect harness connectors for the following conditions: |
| - | Backed out terminals |
| - | Improper mating |
| - | Broken locks |
| - | Improperly formed or damaged terminals |
| - | Poor terminal to wire connection |
| • | Damaged harness -- Inspect the wiring harness for damage. If the harness appears to be OK, observe the MAP display on the scan tool while moving connectors and wiring harnesses related to the sensor. A change in the display will indicate the location of the malfunction. |
If the DTC cannot be duplicated and is determined to be intermittent, reviewing the Failure Records can be useful in determining when the DTC was last set. Also refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.
Test Description
The number below refers to the step number on the diagnostic table:
Step | Action | Values | Yes | No |
1 | Did you perform the Powertrain On-Board Diagnostic (OBD) System Check? | -- | ||
2 |
Important:: Refer to DTC P1635 5 Volt Reference Circuit first, if set:
Does the MAP voltage measure less then the specified value? | 0.1 V | ||
3 |
Does the scan tool indicate DTC P0107 failed? | -- | Go to Diagnostic Aids | |
4 |
Does the MAP voltage measure near the specified value? | 4.95 V | ||
5 |
Does the MAP voltage measure near the specified value? | 4.95 V | ||
6 |
Did you find and correct the condition? | -- | ||
7 | Test the 5 volt reference A circuit of the MAP sensor for a poor connection at the PCM and replace terminal if necessary. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | ||
8 |
Did you find and correct the condition? | -- | ||
9 | Test the signal circuit and the 5 volt reference circuit of the MAP sensor for a poor connection at the MAP sensor and replace the terminal as necessary. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | ||
10 | Test the signal circuit and the 5 volt reference circuit of the MAP sensor for a poor connection at the PCM and replace terminal as necessary. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. 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:: Perform the set up procedure for the PCM. Refer to Powertrain Control Module Replacement/Programming . Replace the PCM. Did you complete the replacement? | -- | -- | ||
13 |
Does the DTC reset? | -- | System OK |
