Manifold Pressure/Vacuum Sensor: Testing and Inspection

MAP Sensor Circuit:

COMPONENT TEST

1. Test the Manifold Absolute Pressure (MAP) sensor output voltage at the MAP sensor connector terminal 2. With the ignition switch ON, and the engine OFF, output voltage should be 4 to 5 volts.

2. Test the MAP sensor output voltage at the MAP sensor connector terminal 2 at a hot, neutral idle speed condition. The voltage should drop to 1.5 to 2.1 volts.


HARNESS TEST

1. Disconnect the MAP Sensor connector.
2. Using an ohmmeter, check for continuity between terminal 3 of the MAP sensor connector and ground.

Continuity:
Should exist

3. Disconnect the Engine Control Module connector.
4. Using an ohmmeter, check for continuity between terminal 2 of the MAP sensor connector and ground.

Continuity:
Should not exist


5. Reconnect the Engine Control Module connector.
6. Turn the ignition switch to the ON position.
7. Using a voltmeter, measure the voltage between terminal 1 and ground.

Voltage:
4.5 - 4.9 Volts.

If any of the previous tests produce unsatisfactory results, the harness will need to be repaired or replaced. Once repairs have been completed, clear the trouble codes and road test the vehicle to confirm that the repair has corrected the problem and the code doesn't return.
If the same trouble code reoccurs, it is possible that there is an intermittent failure of the component or the ECM. Check for looseness at all harness junctions and test for an intermittent failure.