Circuit Description
The manifold absolute pressure (MAP) sensor is a pressure sensor. The control module supplies the MAP sensor a reference voltage, signal, and ground circuits. When manifold vacuum is low, the MAP sensor signal voltage rises to a value near the reference voltage, and the MAP sensor signal voltage decreases when the manifold vacuum increases. The control module monitors the MAP sensor signal circuit voltage in order to calculate the vacuum within the intake manifold.
Certain vehicle models will also use the MAP sensor in order to calculate the barometric pressure (BARO) when the ignition switch is turned ON and the engine is NOT cranked. This BARO reading may also be updated whenever the engine is operated at wide open throttle (WOT).
This DTC is designed to detect MAP signal voltages lower than possible in a normally operating MAP sensor.
Conditions for Running the DTC
| • | No active TP sensor DTCs |
| • | The engine is running |
| • | The throttle position is greater than 0 % with an engine speed below 800 RPM |
| OR |
| The throttle position is greater than 12.5 % with an engine speed above 800 RPM |
Conditions for Setting the DTC
The MAP voltage is below 0.04 volt for more than 1 second.
Action Taken When the DTC Sets
The VCM turns ON the MIL when DTC P0107 is reported and 1 failure has occurred. The VCM substitutes a calculated value for the MAP sensor value so an acceptable driving condition is maintained.
Conditions for Clearing the MIL or DTC
| • | The control module turns OFF the MIL after 3 consecutive drive trips when the test has run and passed. |
| • | A history DTC will clear if no fault conditions have been detected for 40 warm-up cycles. A warm-up cycle occurs when the coolant temperature has risen 22°C (40°F) from the startup coolant temperature and the engine coolant reaches a temperature that is more than 70°C (158°F) during the same ignition cycle. |
| • | Use a scan tool in order to clear the DTCs. |
Diagnostic Aids
An intermittent open in the MAP sensor signal circuit or the 5 volt reference circuit will result in a DTC P1107.
With the ignition ON and the engine OFF, the manifold pressure is equal to the atmospheric pressure with the signal voltage high. The VCM uses this information as an indication of the altitude of the vehicle.
Important: The electrical connector must remain securely fastened.
Important: After removing the MAP sensor from the intake manifold, replace the MAP Sensor to intake manifold seal.
Remove the MAP sensor. Twist the sensor by hand (only) in order to check for intermittent connections. Output changes greater than 0.1 volt indicates a bad connector or connection. If OK, replace sensor.Test Description
The numbers below refer to the step numbers on the diagnostic table.
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This step determines if DTC P0107 is the result of a hard failure or an intermittent condition.
-
By jumping the 5 volt reference to the signal circuit, this step determines if the sensor is at fault, or if there is a problem with the VCM or wiring.
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The scan tool may not display 5 volts. The important thing is that the VCM recognized the voltage as more than 4 volts, indicating that the VCM and MAP signal circuit are OK.
-
The VCM terminals GR 12 and GR 27 are spliced together inside the VCM. When checking the 5 volt reference for a short to ground, both the 5 volt reference circuits and all the components on the 5 volt reference circuits must also be checked.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 |
Important: Before clearing the DTCs, use the scan tool in order to record the Freeze Frame and the Failure Records for reference. This data will be lost when the Clear DTC Information function is used. Was the Powertrain On-Board Diagnostic (OBD) System Check performed? | -- | ||
Does the scan tool display a MAP sensor voltage less than the specified value? | 0.25 V | |||
Does the scan tool display a MAP sensor voltage greater then the specified value? | 4.7 V | |||
Does the scan tool display a MAP sensor voltage greater the specified value? | 4.7 V | |||
5 | The DTC is intermittent. Are any additional DTCs stored? | -- | Go to The Applicable DTC Table. | Go to Diagnostic Aids |
6 | Check for a faulty connection at the MAP sensor. Was a problem found? | -- | ||
7 | Check for an open MAP sensor signal circuit. Was a problem found? | -- | ||
8 | Check the MAP sensor signal circuit for a short to ground or poor connections at the VCM connectors. Was a problem found? | -- | ||
9 | Check for an open in the MAP sensor 5 volt reference circuit. Was a problem found? | -- | ||
Check for a short to ground in the MAP sensor 5 volt reference circuit or poor connections at the VCM connectors. Was a problem found? | -- | |||
11 | Replace the MAP sensor. Refer to Manifold Absolute Pressure Sensor Replacement in Repair Instructions. Is the action complete? | -- | -- | |
12 | Repair the circuit as necessary. Refer to Wiring Repairs in Repair Instructions. | -- | -- | |
13 |
Is the action complete? | -- | -- | |
14 |
Does the scan tool indicate that this diagnostic ran and passed? | -- | ||
15 | Use the scan tool in order to display the Capture Info and the Review Capture Info functions. Are there any DTCs displayed that have not been diagnosed? | -- | Go to The Applicable DTC Table | System OK |
