Toyota Prius 2002-06

Engine

Print

Removal & Installation




CAUTION
The hybrid system uses high voltage circuits, so improper handling could cause electric shock or leakage. During service, be sure to follow procedures.

  1. Before servicing the vehicle, refer to the Precautions Section.
  2.  
  3. Drain engine coolant, engine oil and transaxle fluid.
  4.  
  5. Properly relieve the fuel system pressure.
  6.  
  7. Disconnect the negative battery cable. Wait at least 90 seconds after disconnecting the negative battery cable to prevent possible airbag and seat belt pretensioner activation.
  8.  
  9. While wearing insulating gloves, slide up the lever of the service plug grip and remove while turning the lever to the left. Be sure to insulate the service plug with insulating tape.
    CAUTION
    Do not touch the high voltage connectors and terminals for 5 minutes after removing the service plug grip.

  10.  
  11. Drain the HV coolant.
  12.  
  13. Remove the outer cowl top panel.
  14.  
  15. While wearing insulating gloves, remove the converter and inverter assembly as follows:


    1. Disconnect the battery power cable connector and insulate it with packaging tape.
    2.  
    3. Remove the inverter terminal cover.
    4.  
    5. Disconnect the circuit breaker sensor by first moving the outer cover section away toward the wire side.
    6.  
    7. Remove the circuit breaker sensor.
    8.  
    9. Verify that there is 0V by measuring the voltage between the terminals of the three phase connector (U-V, V-W, U-W), using a voltmeter at each terminal and body ground.
    10.  
    11. Remove the mounting bolts and disconnect the MG1 and MG2 power cables. Protect the connector parts with insulating tape.
    12.  
    13. Disconnect the ground cable.
    14.  
    15. Disconnect the 3 water hoses from the converter and inverter assembly.
    16.  
    17. Remove the 4 mounting bolts and the converter and inverter assembly.
    18.  

  16.  
  17. Remove the heater unit water pump as follows:


    1. Disconnect the connector and wire harness clamp.
    2.  
    3. Disconnect the hoses from the water pump.
    4.  
    5. Remove the bolt and refrigerant line bracket.
    6.  
    7. Remove the 3 bolts and remove the heater unit water pump.
    8.  

  18.  
  19. Remove or disconnect the following:

    Air cleaner assembly
     
    Engine wire clamps
     
    Heated oxygen sensor connector
     
    Power steering connectors
     
    Vacuum Switching Valve (VSV) connector for purge line
     
    VSV hose for purge line
     
    Ground straps from the left and right fender aprons
     
    Air cleaner inlet hose
     
    Engine coolant reservoir tank
     
    Upper and lower radiator hoses from radiator
     
    Heater hose from cylinder block
     
    Shift lever cable
     
    Brake fluid level sensor connector
     
    Brake fluid reservoir tank mounting bolts (2) and suspend it with rope
     
    Electronic Control Module (ECM) located behind glove box
     
    Grommet from cowl panel and pull out engine wire
     
    Junction box No. 1 from right fender apron
     
    Fuel tube from fuel pump
     
    Accessory drive belt
     
    Engine under covers
     
    Wiring harness from A/C compressor
     
    A/C compressor unit from engine. Secure the A/C compressor, still connected to the high- and low-pressure hoses, to the side of the vehicle with rope.
     

  20.  
  21. Disconnect the intermediate extension from the steering assembly as follows:


    1. Hold the steering wheel in the straight ahead position, using the seat belt looped through the steering wheel and buckled securely so the steering wheel will not turn. This will prevent an open circuit of the spiral cable.
    2.  
    3. Remove the 3 clips, then remove the column hole cover.
    4.  
    5. Put paint marks on the No. 2 intermediate shaft assembly and control valve shaft.
    6.  
    7. Loosen the bolt on the steering gear side of the intermediate shaft.
    8.  
    9. Remove the bolt on the steering column side of the intermediate shaft.
    10.  
    11. Disconnect the intermediate shaft assembly from the control valve shaft.
    12.  

  22.  
  23. Remove or disconnect the following:

    Front exhaust pipe
     
    Left and right tie rod ends
     
    Front stabilizer bar links
     
    Left and right ball joints from front lower control arms
     
    Left and right drive shafts
     
    Torque rod
     
    Front suspension crossmember
     

  24.  
  25. Secure the engine/transaxle assembly onto a lifting device.
  26.  
  27. Remove the 2 bolts and nuts and disconnect the right engine mounting insulator from the bracket.
  28.  
  29. Remove the nut and disconnect the left engine mounting from the insulator.
  30.  
  31. While operating the engine lifter, lower the engine and transaxle assembly out of the vehicle slowly and carefully. Make sure the engine is clear of all wiring, hoses and cables.
  32.  
  33. Separate the engine from the transaxle unit.

    Click image to see an enlarged view

    Fig. Remove/install the engine using an engine lifting device-Prius

  34.  

To install:

  1. Connect the transaxle assembly to the engine assembly.
  2.  
  3. Install the engine and transaxle assembly into the engine compartment using the engine lifting device. Keep the engine level and align the right and left mountings with the insulator.
  4.  
  5. Install or connect the following:

    Left mounting bracket to the insulator. Torque the nut to 59 ft. lbs. (80 Nm)
     
    Right mounting bracket to the insulator. Torque the nuts and bolts to 38 ft. lbs. (52 Nm)
     
    Front suspension crossmember. Torque the left and right front corner bolts to 83 ft. lbs. (113 Nm). Torque the left and right rear corner bolts to 116 ft. lbs. (157 Nm).
     
    Torque rod. Torque the 2 nuts and 2 bolts, at the engine, to 74 ft. lbs. (100 Nm). Torque the 2 bolts, at the body side, to 44 ft. lbs. (60 Nm).
     
    Left and right drive shafts
     
    Left and right ball joints to the front lower control arms. Torque to 105 ft. lbs. (142 Nm).
     
    Front stabilizer bar links. Torque to 55 ft. lbs. (74 Nm).
     
    Left and right tie rod ends
     
    Front exhaust pipe with the gaskets and O-rings. Torque the 3 exhaust pipe bolts to 46 ft. lbs. (62 Nm).
     

  6.  
  7. Connect the intermediate extension to the steering assembly as follows:


    1. Align the paint marks on the No. 2 intermediate shaft assembly and control valve shaft.
    2.  
    3. Install the bolt on the steering column side of the intermediate shaft.
    4.  
    5. Tighten the bolts to 26 ft. lbs. (35 Nm).
    6.  
    7. Install the column hole cover with the 3 clips.
    8.  
    9. Remove the seat belt from the steering wheel.
    10.  

  8.  
  9. Install or connect the following:

    A/C compressor unit to the engine. Torque the 4 mounting bolts to 18 ft. lbs. (25 Nm).
     
    Wiring harness to the compressor
     
    Accessory drive belt
     
    Fuel tube to the fuel pump
     
    Junction box No. 1 to the right fender apron
     
    Engine wire to cowl panel and connect grommet
     
    Electronic Control Module (ECM) located behind glove box
     
    Brake fluid reservoir tank and mounting bolts
     
    Brake fluid level sensor connector
     
    Shift lever cable to transaxle
     
    Heater hose to cylinder block
     
    Upper and lower radiator hoses to the radiator
     
    Engine coolant reservoir tank
     
    Air cleaner inlet hose
     
    Ground straps to the left and right fender aprons
     
    VSV hose for purge line
     
    VSV connector for purge line
     
    Power steering connectors
     
    Heated oxygen sensor connector
     
    Engine wire clamps
     
    Air cleaner assembly
     

  10.  
  11. Install the heater unit water pump as follows:


    1. Install the heater unit water pump. Torque the 3 mounting bolts to 48 inch lbs. (5.4 Nm).
    2.  
    3. Install the bolt and refrigerant line bracket.
    4.  
    5. Connect the hoses to the water pump.
    6.  
    7. Connect the connector and wire harness clamp.
    8.  

  12.  
  13. While wearing insulating gloves, install the converter and inverter assembly as follows:


    1. Install the converter and inverter assembly and torque the 4 mounting bolts to 15 ft. lbs. (21 Nm).
    2.  
    3. Connect the 3 water hoses to the converter and inverter assembly.
    4.  
    5. Connect any remaining wiring connectors.
    6.  
    7. Connect the ground cable.
    8.  
    9. Connect the MG1 power cable and 3 mounting bolts. Torque the 3 mounting bolts to 62 inch lbs. (7 Nm).
    10.  
    11. Connect the 3 MG2 power cables and 6 mounting bolts. Torque the A mounting bolts to 14 ft. lbs. (19.5 Nm), and the B mounting bolts to 71 inch lbs. (8 Nm).

      Click image to see an enlarged view

      Fig. MG2 power cables and mounting bolts-2002-03 Prius

    12.  
    13. Install the circuit breaker sensor and connector cover. Torque the 2 mounting screws to 15 ft. lbs. (20 Nm).
    14.  
    15. Connect the circuit breaker sensor.
    16.  
    17. Install the inverter terminal cover and gasket. Tighten the 4 screws to 71 inch lbs. (8 Nm).
    18.  

  14.  
  15. Install the outer cowl top panel.
  16.  
  17. Refill with HV coolant.
  18.  
  19. Refill engine cooling system.
  20.  
  21. Install the engine under covers.
  22.  
  23. Connect the negative battery cable and install the HV battery service plug.
  24.  
  25. Refill the engine and transaxle with oil and transaxle fluid.
  26.  
  27. With the converter and inverter assembly removed/installed, check that the inverter operates properly by performing the following:


    1. Disconnect the auxiliary battery for 1 minute or more and then connect it again.
    2.  
    3. Depress accelerator pedal to a degree of 50 percent, increasing the speed up to approximately 15 km/h 3 or 4 times to check that there is no problem in the inverter operation.
    4.  

  28.  
  29. Run the engine and verify that there are no fuel, coolant, transaxle or exhaust leaks. Also check for smooth operation.
  30.  


CAUTION
The hybrid system uses high voltage circuits, so improper handling could cause electric shock or leakage. During service, be sure to follow procedures.

  1. Before servicing the vehicle, refer to the Precautions Section.
  2.  
  3. Drain engine coolant, engine oil and transaxle fluid.
  4.  
  5. Remove the rear No. 2 floor board.
  6.  
  7. Remove the rear deck floor box.
  8.  
  9. Remove the rear No. 3 floor board.
  10.  
  11. Properly relieve the fuel system pressure.
  12.  
  13. Disconnect the negative battery cable. Wait at least 90 seconds after disconnecting the negative battery cable to prevent possible airbag and seat belt pretensioner activation.
  14.  
  15. While wearing insulating gloves, slide up the lever of the service plug grip and remove while turning the lever to the left. Be sure to insulate the service plug with insulating tape.
    CAUTION
    Do not touch the high voltage connectors and terminals for 5 minutes after removing the service plug grip.

  16.  
  17. Remove or disconnect the following:

    Front wheels
     
    Engine under covers
     
    Left and right front wiper arms
     
    Hood-to-cowl top seal
     
    Left and right cowl top ventilator louvers
     
    Windshield wiper motor and link assembly
     
    Front outer cowl top panel

    Click image to see an enlarged view

    Fig. Inverter with converter assembly and related components-2004-06 model shown

     

  18.  
  19. While wearing insulating gloves, remove the inverter with converter assembly as follows:


    1. Remove the left and right engine under covers.
    2.  
    3. Drain the HV coolant.
    4.  
    5. Remove the radiator support opening cover.
    6.  
    7. Remove the inverter cover.
    8.  
    9. Verify that there is 0V at the inverter with converter, using a voltmeter utilizing a measuring range of DC 400V or more.

      Click image to see an enlarged view

      Fig. Verifying that there is 0V at the inverter with converter-Prius

    10.  
    11. Again, verify that there is 0V by measuring the voltage between the terminals of the three phase connector (U-V, V-W, U-W), using a voltmeter utilizing a measuring range of DC 400V or more.

      Click image to see an enlarged view

      Fig. Measuring voltage between the terminals of the three phase connector-Prius

    12.  
    13. Disconnect the No. 1, No. 2 and No. 6 inverter cooling hoses.
    14.  
    15. Disconnect the No. 1 circuit breaker sensor by first moving the outer section away toward the wire side.
    16.  
    17. Disconnect the 2 frame wire connectors from the inverter with converter assembly and protect the electrode and connector parts with insulating tape.
    18.  
    19. Use a small screwdriver to lift up the green lock pin, then disconnect the connector for the air conditioning inverter.
    20.  
    21. Disconnect any remaining wiring connectors including the engine main wiring harness.
    22.  
    23. Remove the mounting bolts and disconnect the MG1 and MG2 power cables. Protect the connector parts with insulating tape.
    24.  
    25. Remove the 3 mounting bolts and the inverter with converter assembly.
    26.  

  20.  
  21. Remove or disconnect the following:

    Radiator assembly
     
    No. 3 inverter cooling hose
     
    No. 1 heat storage water by-pass hose
     
    Engine ground cable
     
    Air cleaner inlet hose from air cleaner case
     
    Air cleaner assembly
     
    Vacuum Switching Valve (VSV) assembly
     
    Fuel pipe clamp
     
    Fuel tube from fuel delivery pipe by pinching the quick connector with your hand and pulling
     
    Heater water hose
     
    No. 3 heat storage water by-pass hose
     
    Connector from ECM, then pull engine wire harness toward the engine compartment side
     
    Harness and harness clamp from the engine room main relay block
     
    Ground cable
     
    Wiring harness from compressor
     
    Compressor unit from engine. Secure the compressor, still connected to the high- and low-pressure hoses, to the side of the vehicle with rope.
     

  22.  
  23. Disconnect the steering sliding yoke as follows:


    1. Hold the steering wheel in the straight ahead position, using the seat belt looped through the steering wheel and buckled securely so the steering wheel will not turn. This will prevent an open circuit of the spiral cable.
    2.  
    3. Remove the 2 clips, then remove the column hole cover silencer.
    4.  
    5. Loosen the bolt on the steering column side of the sliding yoke.
    6.  
    7. Remove the bolt on the steering gear side of the sliding yoke.
    8.  
    9. Put paint marks on the sliding yoke and intermediate shaft, then disconnect the sliding yoke.
    10.  

  24.  
  25. Remove or disconnect the following:

    Front exhaust pipe
     
    Left and right front axle hub nuts
     
    Left front stabilizer link
     
    Left and right tie rod ends
     
    Left and right front lower control arms
     
    Left and right front axle hub/bearing assemblies
     
    Left and right drive shafts
     
    Engine torque rod
     
    Front suspension crossmember
     

  26.  
  27. Secure the engine/transaxle assembly onto a lifting device.
  28.  
  29. Remove or disconnect the following:

    Right engine mounting bracket and right engine mounting insulator
     
    Left engine mounting bracket and left engine mounting insulator
     

  30.  
  31. While operating the engine lifter, lower the engine and transaxle assembly out of the vehicle slowly and carefully. Make sure the engine is clear of all wiring, hoses and cables.
  32.  
  33. Separate the engine from the transaxle unit.

    Click image to see an enlarged view

    Fig. Remove/install the engine using an engine lifting device-Prius

  34.  

To install:

  1. Connect the transaxle assembly to the engine assembly.
  2.  
  3. Install the engine and transaxle assembly into the engine compartment using the engine lifting device.
  4.  
  5. Install or connect the following:

    Right engine mounting bracket and right engine mounting insulator. Torque the nuts and bolts to 38 ft. lbs. (52 Nm)
     
    Left engine mounting bracket and left engine mounting insulator. Torque the nut to 59 ft. lbs. (80 Nm)
     
    Front suspension crossmember. Torque the left and right front corner bolts to 83 ft. lbs. (113 Nm). Torque the left and right rear corner bolts to 116 ft. lbs. (157 Nm).
     
    Engine torque rod. Torque the 2 nuts and 2 bolts, at the engine, to 74 ft. lbs. (100 Nm). Torque the 2 nuts and 2 bolts, at the body side, to 41 ft. lbs. (56 Nm).
     
    Left and right drive shafts
     
    Left and right front axle hub/bearing assemblies
     
    Left and right front lower control arms
     
    Left and right tie rod ends
     
    Left front stabilizer link
     
    New left and right front axle hub nuts and torque to 159 ft. lbs. (216 Nm). Using a chisel and hammer, stake the hub nut.
     
    Front exhaust pipe
     

  6.  
  7. Connect the steering sliding yoke as follows:


    1. Align the paint marks on the sliding yoke and intermediate shaft, then connect the sliding yoke.
    2.  
    3. Torque the sliding yoke bolts to 26 ft. lbs. (35 Nm).
    4.  
    5. Install the column hole cover silencer with the 2 clips.
    6.  
    7. Remove the seat belt from the steering wheel.
    8.  

  8.  
  9. Install or connect the following:

    Compressor unit to the engine. Torque the three mounting bolts to 18 ft. lbs. (25 Nm).
     
    Wiring harness to the compressor
     
    Ground cable
     
    Harness and harness clamp to the engine room main relay block
     
    Wire harness connector to the ECM
     
    No. 3 heat storage water by-pass hose
     
    Heater water hose
     
    Fuel tube to the fuel delivery pipe by pushing the quick connector until it makes a -click- sound. Check to make sure the connection is secure by gently, but firmly pulling on it.
     
    Fuel pipe clamp
     
    VSV assembly. Torque bolt to 5.5 ft. lbs. (7.5 Nm).
     
    Air cleaner assembly
     
    Air cleaner inlet hose to the air cleaner case
     
    Engine ground cable
     
    No. 1 heat storage water by-pass hose
     
    No. 3 inverter cooling hose
     
    Radiator assembly
     

  10.  
  11. While wearing insulating gloves, install the inverter with converter assembly as follows:


    1. Install the inverter with converter assembly and tighten the three mounting bolts to 16 ft. lbs. (21 Nm).
    2.  
    3. Connect the MG1 and MG2 power cables and tighten the mounting bolts to 71 inch lbs. (8 Nm).
    4.  
    5. Connect any remaining wiring connectors including the engine main wiring harness. Be sure to insert the grommet of the engine main wiring harness into the U-shaped groove of the inverter case.
    6.  
    7. Engage the connector for the air conditioning inverter and secure by pushing in the lock pin..
    8.  
    9. Connect the 2 frame wire connectors to the inverter with converter assembly.
    10.  
    11. Connect the No. 1 circuit breaker sensor.
    12.  
    13. Connect the No. 6, No. 2 and No. 1 inverter cooling hoses.
    14.  
    15. Install the inverter cover and tighten the mounting fasteners to 8 ft. lbs. (11 Nm).
    16.  
    17. Install the radiator support opening cover.
    18.  
    19. Install the left and right engine under covers.
    20.  

  12.  
  13. Install or connect the following:

    Front outer cowl top panel
     
    Windshield wiper motor and link assembly
     
    Left and right cowl top ventilator louvers
     
    Hood-to-cowl top seal
     
    Left and right front wiper arms
     

  14.  
  15. While wearing insulating gloves, joint the service plug grip with the HV battery. While pushing the service plug grip to the right, rotate the lever to the right. Slide the lever down to lock the service plug grip in place.
  16.  
  17. Connect the negative battery cable.
  18.  
  19. Install the rear No. 3 floor board.
  20.  
  21. Install the rear deck floor box.
  22.  
  23. Install the rear No. 2 floor board.
  24.  
  25. Refill engine coolant, engine oil and transaxle fluid.
  26.  
  27. Install or connect the following:

    Front wheels
     
    Engine under covers
     

  28.  
  29. Adjust front wheel alignment.
  30.  
  31. Perform initialization.
  32.  
  33. Run the engine and verify that there are no fuel, coolant, transaxle or exhaust leaks.
  34.  

 
label.common.footer.alt.autozoneLogo