P1408

DTC P1408 MANIFOLD DIFFERENTIAL PRESSURE SENSOR CIRCUIT MALFUNCTION





WIRING DIAGRAM






DETECTING CONDITION






DTC CONFIRMATION PROCEDURE

WARNING:
- When performing a road test, select a place where there is no traffic or possibility of a traffic accident and be very careful during testing to avoid occurrence of an accident.
- Road test should be carried out with 2 persons, a driver and a tester, on a level road.

NOTE: Check to make sure that following condition is satisfied when using this DTC CONFIRMATION PROCEDURE.

Intake air temp: higher than 5°C (41°F).





TROUBLESHOOTING





TROUBLESHOOTING (SIGNAL VOLTAGE LOW)





TROUBLESHOOTING (SIGNAL VOLTAGE HIGH)

Manifold Differential Pressure Sensor Check
1) Disconnect manifold differential pressure sensor vacuum hose from filter.
2) Disconnect manifold differential pressure sensor coupler.
3) Remove manifold differential pressure sensor.
4) Arrange 3 new 1.5V batteries in series and connect its positive terminal to "Vin" terminal of coupler 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.





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





If check result is not satisfactory, replace manifold differential pressure sensor.
5) Install manifold differential pressure sensor and connect vacuum hose securely.
6) Connect manifold differential pressure sensor coupler securely.