ABNORMALITY IN CHARACTERISTICS OF THE DPR DIFFERENTIAL PRESSURE SENSOR (DTC CODE P1426 / DIAGNOSIS MONITOR CODE 28)

1. Check that the differential pressure sensor connector is properlyinstalled.
   
   

NO Improper connection of connector	YES Proceed to [2] Check whether the sensor is in normal condition

1. Troubleshoot the P1427 and P1428 and check whether the differential pressure sensor is in normal condition.
   

NO Fault in differential pressure sensor	YES Proceed to [3] Check the differential pressure hose for damage

NO Replacement of the differential pressure hose	YES Proceed to [4] Check whether the clamp is in normal condition

NO Replacement of the clamp	YES Proceed to [5] Check that the differential pressure pipe is internally clogged

NO Internal cleaning of the differential pressure pipe	YES Proceed to [6] Check whether other are in normal condition

1. If the GND terminal is shared in use, disconnect all sensor connectors that use the GND terminal and check whether condition is normal.
   
   

NO Fault in engine ECU	YES Fault in other sensors

1. Confirm the DTC P1426 is inactive

   • Start the engine and let it idling condition.
   • Verify the DTC P1426 is inactive.

   

2. DTC Clear

   • Clear the DTC with Hino DX
   • Confirm the same DTC is not reoccurred

   

P1426 is reoccur: Return to first process Other DTC appear: Refer to concerned Trouble shooting

Complete