The manifold absolute pressure (MAP) sensor responds to pressure changes in the intake manifold. The pressure changes occur based on the engine load. 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 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 throttle position (TP) sensor is more than 28 percent. The MAP sensor contains the following circuits:

If the ECM detects that the MAP sensor pressure/voltage is intermittently too low, this DTC sets.

This diagnostic procedure supports the following DTC:

DTC P1107 Manifold Absolute Pressure (MAP) Sensor Circuit Intermittent Low Voltage

The ECM detects that the MAP sensor is less than 12 kPa intermittently for a total of 2 seconds during a 60 second time period.

The numbers below refer to the step numbers on the diagnostic table.

3. This step attempts to determine if the intermittent fault is a connector.

4. This step attempts to determine the location of the intermittent fault.