System description

 

ENGINE CONTROL SYSTEM

ECD SYSTEM > System description 2AD-FHV Engine control TOYOTA RAV4 / ACA30, 33, 38 ALA30



 

TOYOTA D-CAT DESCRIPTION


  1. Diesel Clean Advanced Technology (TOYOTA D-CAT) comprehensively regulates engine control (consists of a catalytic system and a fuel injection system) that purifies both particulate matter (PM) and nitrogen oxides (NOx) discharged by diesel engines. The catalytic system purifies hydrocarbons (HC) and carbon monoxides (CO), and reduces PM and NOx with a catalytic converter with the Diesel Particulate-NOx Reduction system (DPNR). The fuel injection system adds fuel into the exhaust port using the exhaust fuel addition injector to produce a RICH state for NOx reduction and maintain a proper catalyst temperature for DPNR catalyst regeneration.


    ECD SYSTEM > System description 2AD-FHV Engine control TOYOTA RAV4 / ACA30, 33, 38 ALA30

     

  2. TOYOTA D-CAT components:
     

    ComponentDescription
    DPNR catalytic converterReduces HC, CO, PM, and NOx.
    Exhaust fuel addition injectorAdds fuel into the exhaust port in order to produce RICH air-fuel ratio for NOx reduction. Also, raises catalyst temperature for DPNR catalyst regeneration.
    Exhaust gas temperature sensorUsed for estimating DPNR catalytic converter temperature and adjusting fuel addition by ECM while DPNR catalyst regeneration is performed. Also, detects DPNR catalytic converter temperature to prevent the catalytic converter temperature from rising too high.
    Differential pressure sensorDetects the volume of PM deposits and incorrect vacuum hose arrangement on the DPNR catalytic converter.
    A/F sensorUsed for controlling air-fuel ratio. By controlling the air-fuel ratio, combustion control for low temperature combustion and DPNR catalyst regeneration are properly regulated.

     

  3. Diagnostic Trouble Codes (DTCs) table for TOYOTA D-CAT:

    УКАЗАНИЕ:

    This table indicates typical DTC combinations for each malfunction occurrence.

     


    Trouble AreaMalfunctionDTC No.
    DPNR catalytic converterDeteriorated or cloggedP2002, P1601, P1386*
    Exhaust fuel addition injectorStuck openP1386
    Stuck closedP1386, P2002*
    Low fuel addition volumeP1386, P2002*
    Open in exhaust fuel addition injector circuitP1386, P2047, P2002*
    Short in exhaust fuel addition injector circuitP1386, P2047
    Open or short in exhaust fuel addition injectorP1386, P2047, P2002*
    Exhaust gas temperature sensorOpen in exhaust gas temperature sensor circuitP0544, P0545, P0546, P1386, P2031, P2032, P2033
    Short in exhaust gas temperature sensor circuitP0544, P0545, P0546, P1386*, P2002*, P2031, P2032, P2033
    Exhaust gas temperature sensorP0544, P0545, P0546, P1386*, P2031, P2032, P2033
    Differential pressure sensorOpen in differential pressure sensor circuitP1425, P1427, P2002*
    Short in differential pressure sensor circuitP1425, P1427, P2002*
    Differential pressure sensorP1425, P1427, P2002*
    Differential pressure sensor cloggedP1426, P2002*
    Incorrect vacuum hose arrangement of the differential pressure sensorP1426, P2002*
    A/F sensorOpen or short in A/F sensor or heater circuitP0031, P0032, P1386*, P2238, P2239, P2252, P2253
    A/F sensorP0031, P0032, P1386*, P2238, P2239, P2252, P2253
    Exhaust gas leaksExhaust gas leaksP1386*, P2002*
    Fuel leaksFuel leaks in fuel addition injectorP1386*
    Supply pumpCorrect fuel pressure cannot be fed to the exhaust fuel addition injectorP1386*

    УКАЗАНИЕ:

    *: There may be no DTC output depending on the condition of the malfunction.

     

     

  4. Diagnostic trouble code description for TOYOTA D-CAT:
     

    DTC No.Description
    P0031Open or short in A/F sensor heater control circuit (low output)
    P0032Open or short in A/F sensor or heater circuit (high output)
    P0544Open or short in exhaust gas temperature sensor circuit (upstream)
    P0545Open or short in exhaust gas temperature sensor circuit (upstream) (low output)
    P1386Open or short in exhaust gas temperature sensor circuit (upstream) (high output)
    P1425TOYOTA D-CAT fuel addition system malfunction
    P1426Differential pressure sensor is clogged or has incorrect vacuum hose arrangement
    P1427Open or short in differential pressure sensor circuit (low output)
    P1428Open or short in differential pressure sensor circuit (high output)
    P2002DPNR catalytic converter malfunction
    P2031Open or short in exhaust gas temperature sensor circuit (downstream)
    P2032Open or short in exhaust gas temperature sensor circuit (downstream) (low output)
    P2033Open or short in exhaust gas temperature sensor circuit (downstream) (high output)
    P2047Open in exhaust fuel addition injector circuit
    P2238Open or short in A/F sensor or heater circuit (low output)
    P2239Open or short in A/F sensor or heater circuit (high output)
    P2252Open or short in A/F sensor or heater circuit (low output)
    P2253Open or short in A/F sensor or heater circuit (high output)

     

COMMON RAIL SYSTEM DESCRIPTION


  1. Common rail system:
    The common rail system uses high-pressure fuel for improved fuel economy. This system also provides robust engine power, while suppressing engine vibration and noise.
    This system stores fuel in the common rail, which has been pressurized and supplied by the supply pump. By storing fuel at high-pressure, the common rail system can provide fuel at stable fuel injection pressures, regardless of engine speed or engine load.
    The ECM, using the EDU, provides an electric current to the piezo actuator in each injector to regulate the fuel injection timing and volume. The ECM also monitors the internal fuel pressure of the common rail using the fuel pressure sensor. The ECM causes the supply pump to supply the fuel necessary to obtain the target fuel pressure.
    In addition, this system uses a piezo actuator inside each injector to open and close the fuel passages. Therefore, both fuel injection time and fuel injection volume can be precisely regulated by the ECM.
    The common rail system allows a two stage fuel injection process. In order to soften combustion shock, this system performs "pilot-injection" prior to the main fuel injection. This helps to reduce engine vibration and noise.


    ECD SYSTEM > System description 2AD-FHV Engine control TOYOTA RAV4 / ACA30, 33, 38 ALA30

     

  2. Common rail system components:
     

    ComponentDescription
    Common railStores high-pressure fuel produced by supply pump
    Supply pumpOperated by crankshaft
    Supplies high-pressure fuel to common rail
    InjectorInjects fuel to combustion chamber based on signals from ECM
    Fuel pressure sensorMonitors internal fuel pressure of common rail and sends signals to ECM
    Pressure Discharge ValveBased on signals from the ECM, opens valve when sudden deceleration has occurred, or when the ignition switch is off to prevent the fuel pressure from becoming too high.
    Suction control valveBased on signals from ECM, adjusts fuel volume supplied to common rail and regulates internal fuel pressure
    Check valveKeeps pressure that discharges from injector

     

  3. Diagnostic trouble codes (DTCs) table for the common rail system

    УКАЗАНИЕ:

    This table indicates typical DTC combinations for each malfunction occurrence.

     


    Trouble AreaMalfunctionDTC No.
    InjectorOpen or short in injector circuitP0200, P1238, P0093*
    Stuck openP0093, P1238
    Stuck closedP1238
    Fuel pressure sensorOpen or short in fuel pressure sensor circuit or pressure sensor output fixedP0087, P0190, P0191, P0192, P0193
    Pressure discharge valveOpen or short in pressure discharge valve circuitP1271, P1272, P0088*, P0093*, P1229*
    Stuck openP0093
    Stuck closedP1272, P0088*
    Suction control valveOpen or short in suction control valve circuitP0627, P1229, P0088*
    Stuck openP1229, P0088*
    EDUFaulty EDUP0093*, P0200*, P1238*, P1271*, P1272*
    Common rail system (fuel system)Fuel leaks in high-pressure areaP0093

    УКАЗАНИЕ:

    *: There may be no DTC output depending on the condition of the malfunction.

     

     

  4. Diagnostic trouble code description for the common rail system:
     

    DTC No.Description
    P0087Fuel pressure sensor output does not change
    P0088Internal fuel pressure too high (200 MPa [2,039 kgf/cm2, 29,007 psi] or more)
    P0093Fuel leaks in high-pressure areas
    P0190Open or short in fuel pressure sensor circuit (output voltage is too low or too high)
    P0192Open or short in fuel pressure sensor circuit (output voltage is too low)
    P0193Open or short in fuel pressure sensor circuit (output voltage is too high)
    P0200Open or short in EDU or injector circuit
    P0627Open or short in suction control valve circuit
    P1229Fuel over-feed
INJECTION CONTROL SYSTEM DESCRIPTION

The ECM controls the fuel injection system through the EDU, injectors, and supply pump.
The ECM determines the injection volume and injection timing based on signals from the acceleration position sensor, crank position sensor, and camshaft position sensor. Based on the signals from the ECM, the EDU controls the injectors. The EDU also controls the suction control valve installed on the supply pump to help regulate fuel pressure.
The piezo type injector used in the 2AD-FHV engine makes noise when the engine is idling because this injector operates at high speed. Therefore, the EDU controls the injector to operate at low speed when the engine is idling based on signals from the ECM to achieve noise reduction.
The feed pump is used to pump fuel from the fuel tank to the supply pump.


ECD SYSTEM > System description 2AD-FHV Engine control TOYOTA RAV4 / ACA30, 33, 38 ALA30



 

SUPPLY PUMP OPERATION SYSTEM DESCRIPTION

The rotation of the eccentric cam in the supply pump causes the ring cam in the supply pump to push plunger A upward as illustrated below. The spring force pulls plunger B (located opposite to plunger A) upward. As a result, plunger B draws the fuel in, and plunger A pumps fuel out at the same time.


ECD SYSTEM > System description 2AD-FHV Engine control TOYOTA RAV4 / ACA30, 33, 38 ALA30


 

SUCTION CONTROL VALVE OPERATION SYSTEM DESCRIPTION

УКАЗАНИЕ:

The ECM controls the suction control valve operation to regulate the fuel volume that is produced by the supply pump for the common rail. This control is performed to regulate the internal fuel pressure of the common rail to the targeted injection pressure.

 



  1. Small opening of the suction control valve:
    (1) When the opening of the suction control valve is small, the volume of supplied fuel is small.
    (2) The suction volume becomes small due to the narrow path despite the plunger stroke being full. The difference between the geometrical volume and suction volume creates a vacuum.
    (3) Pump output will start when the fuel pressure at (A) becomes higher than the common rail pressure (B).


    ECD SYSTEM > System description 2AD-FHV Engine control TOYOTA RAV4 / ACA30, 33, 38 ALA30

     



  2. Large opening of the suction control valve:
    (1) When the opening of the suction control valve is large, the volume of supplied fuel is increased.
    (2) If the plunger stroke is full, the suction volume becomes large because of the wide path.
    (3) Pump output will start when the fuel pressure at (A) becomes higher than the common rail pressure (B).


    ECD SYSTEM > System description 2AD-FHV Engine control TOYOTA RAV4 / ACA30, 33, 38 ALA30