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Manifold Pressure/Vacuum Sensor: Testing and Inspection












MANIFOLD DIFFERENTIAL PRESSURE (MDP) SENSOR


OPERATION
- The Manifold Differential Pressure (MDP) sensor converts air pressures in the intake manifold plenum into voltage signals and sends them to the engine control module.
The engine control module monitors the Exhaust Gas Recirculation (EGR) system using these signals and generates a diagnostic trouble code if there is an abnormality in the EGR system.
- 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





STEP 1. Check for continuity of the ground circuit.
- Manifold differential pressure sensor connector: Disconnected

OK: GO TO STEP 2
NG: Repair the harness. (A2 - 92)






STEP 2. 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. (A1 - 74)






STEP 3. Measure the sensor feed voltage to the manifold differential pressure sensor.
- Manifold differential pressure sensor connector: Disconnected
- Engine control module connector: Connected
- Ignition switch: ON

Voltage: 4.8 - 5.2 V

OK: STOP
NG: Replace the engine control module.