Check Manifold Absolute Pressure Sensor

Using new dry cell batteries, connect the battery positive terminal to terminal No. 3 and the battery ground terminal to terminal No. 1, and connect the circuit tester positive terminal to terminal No. 4 and the circuit tester ground terminal to terminal No. 1.
NOTE:
- Use new dry-cell batteries.
- Using a circuit tester, check that the initial voltage of each dry-cell battery is 1.6 V or more. And also check that the voltage of three batteries in series is between 4.8 - 5.2 V.
- For power supply, 5 V DC constant voltage power source can also be used.
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Check the voltage at a normal atmospheric pressure.

NOTE: The atmospheric pressure at higher altitude is lower than normal. Therefore, the voltage is lower than the standard value.

Terminal No.	Standard
4 (+) and 1 (-)	Approx. 1.7 V (when 25°C (77°F))

Connect the Mighty Vac to the pressure port (A).

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Check the voltage when generating vacuum and positive pressure using Mighty Vac.

CAUTION: Do not apply a vacuum that exceeds -88 kPa (-0.9 kg/cm² , -12.8 psi). Doing so may damage the manifold absolute pressure sensor.

NOTE: When vacuum pressure occurs at the pressure port, the voltage will drop from the value as in step 2. When positive pressure occurs, on the other hand, the voltage will rise.

Pressure	Terminal No.	Standard
-88 kPa (-0.9 kg/cm² , -12.8 psi)	4 (+) and 1 (-)	Approx. 0.4 V (when 25°C (77°F))