Manifold Pressure/Vacuum Sensor: Testing and Inspection

OPERATION
- Manifold differential pressure switch converts the intake manifold plenum pressure to the voltage and inputs to the engine control module. Engine control module confirms the operation of EGR system from this signal and, if there is any error in the EGR system, memorizes the diagnostic trouble code.
- 5 V of power is supplied to the manifold differential pressure sensor from the engine control module and the sensor circuit ground is located in the engine control module.
- The manifold differential pressure sensor output voltage is proportioned to the intake manifold plenum pressure and sent to the engine control module.

INSPECTION





Using Scan Tool

HARNESS INSPECTION





Check for continuity of the ground circuit.
- Manifold differential pressure sensor connector:
Disconnected
OK: GO TO STEP 2
NG: Repair the harness. (A2 - 49)





Check for open-circuit, or short-circuit to ground between the engine control module and the manifold differential pressure sensor.
- Manifold differential pressure sensor connector: Disconnected
- Engine control module connector: Disconnected
OK: GO TO STEP 3
NG: Repair the harness. (A3 - 92)





Measure the impressed voltage to the manifold differential pressure sensor.
- Manifold differential pressure sensor connector: Disconnected
- Engine control module connector: Connected
- Ignition switch: ON
Voltage (V): 4.8 - 5.2
OK: STOP
NG: Repair the engine control module.