TURBOCHARGER OVERBOOST
(DTC CODE P0234 / DIAGNOSIS MONITOR CODE 34)

1. Turn the starter key "ON" and check that other DTC codes (P0045, P0049 and U1123) are not indicated.
2. To check, touch the VNT link with hands.
   

   Standard: The VNT link must be movable with hands.

NO Faulty turbocharger	YES Proceed to [2] Inspection of VNT

1. Use the HINO-DX to inspect the VNT.

Standard value: Followability to a target value must be achieved within 3 seconds.

NO Fault in VNT ECU and/or turbocharger	YES Proceed to [3] Inspecting exhaust system components/parts

1. Inspect exhaust system components/parts.
   

   Standard: No clogging or unauthorized modification is allowed.

NO Fault in exhaust system components/parts	YES Proceed to [4] Inspecting the boost pressure sensor hose

1. Inspect a boost pressure sensor hose.
   

   Standard: No looseness or abnormality is allowed.

NO Fault in boost pressure sensor hose	YES Inspection of EGR valve

1. Confirm the DTC P0234 is inactive

   • Start the engine and let it idling condition.
   • Verify the DTC P0234 is inactive.

   

2. DTC Clear

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

   

P0234 is reoccur: Return to first process Other DTC appear: Refer to concerned Trouble shooting

Complete