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Manifold Pressure/Vacuum Sensor: Testing and Inspection

Manifold Absolute Pressure (MAP) Sensor Inspection

Reference: Manifold Absolute Pressure (MAP) Sensor Removal and Installation

1. Check sensor O-ring (1) for damage and deterioration. Replace as necessary.






2. Arrange new three 1.5 V batteries (2) in series and connect its positive terminal to "Vin" terminal and negative terminal to "Ground" terminal. Then, check voltage between "Vout" and "Ground". Also, check if voltage reduces when vacuum is slowly applied up to 400 mmHg by using vacuum pump (3). If check result is not satisfactory, replace manifold absolute pressure sensor (1).

CAUTION: As connection to wrong terminal will cause damage to manifold absolute pressure sensor, make absolutely sure to connect properly as shown in the figure.

Manifold absolute pressure output voltage ("Vin" voltage: 4.7 - 5.5 V, ambient temp. 20 - 30°C (68 - 86°F))