Code No. P1273: Supply Pump Insufficient Flow


OPERATION



  • Refer to Code No. P0335: Crank Angle Sensor System .
  • Refer to Code No. P0340: Camshaft Position Sensor System .
  • Refer to Code No. P0628: Suction Control Valve Open <Euro3, Euro4> .
  • Refer to Code No. P0629: Suction Control Valve Battery Short <Euro3, Euro4> .
  • Refer to Code No. P0003: Suction Control Valve Open <Euro5> .
  • Refer to Code No. P0004: Suction Control Valve Battery Short <Euro5> .

FUNCTION



  • The engine-ECU controls the fuel discharge rate using the suction control valve.
  • The engine-ECU monitors changes in the fuel discharge rate at each injection to detect a fault in one of the two plungers in the supply pump.

TROUBLE JUDGMENT


Check Condition
  • Vehicle in steady and stable state (the difference from the last data of the objective common rail pressure is less than 3 MPa and that from the last data of the final fuel injection rate is less than 2 mm3/st.
Judgment Criterion
  • The inter-cylinder difference in pressure feed exceeds the predetermined value 100 times consecutively.

PROBABLE CAUSES



  • Air penetration due to lack of fuel
  • Failed supply pump
  • Failed engine-ECU

DIAGNOSIS PROCEDURE
note This diagnosis code is set for an air penetration in the fuel line of the supply pump due to lack of fuel. Therefore, bleed air from the fuel line after the fuel supply, and delete the diagnosis code through M.U.T.-III.

STEP 1. M.U.T.-III diagnosis code

  • With the air released from the fuel line, supply fuel if necessary.
  • Continue idle operation for about 5 minutes.

Q. Is diagnosis code P1273 set again?
Go to Step 2.
The check is end.

STEP 2. Replace the supply pump assembly.

  • After the supply pump assembly, learn the supply pump (Refer to GROUP 00 - Precautions Before Service - What The Common Rail Engine Learns ).
  • After replacing the supply pump assembly, re-check the trouble symptoms

Q. Does trouble symptom persist?
Replace the engine-ECU. When the engine-ECU is replaced, write the chassis number (Refer to GROUP 00 - Precautions Before Service - How to Perform Chassis Number Writing ). After replacing the engine-ECU, register the injector identification code and learn fuel injection (Refer to GROUP 00 - Precautions Before Service - What The Common Rail Engine Learns ). After registering the injector identification code, the vehicle equipped with the closed type DPF carries out the forcible DPF regeneration. (Refer to GROUP 17 - Diesel Particulate Filter (DPF) System - Forcible DPF Regeneration ).
The check is end.