Repair Instruction: Precaution

1. HINTS ON OPERATIONS
   Fig 1: Identifying Basic Repair Instruction

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2. JACKING UP AND SUPPORTING VEHICLE
   1. Care must be taken when jacking up and supporting the vehicle. Be sure to lift and support the vehicle at the proper locations.
3. PRECOATED PARTS
   1. Precoated parts are bolts and nuts that are coated with a seal lock adhesive at the factory.
   2. If a precoated part is retightened, loosened or moved in any way, it must be recoated with the specified adhesive.
   3. When reusing a precoated part, clean off the old adhesive and dry the part with compressed air. Then apply new seal lock adhesive appropriate to that part.
   4. Some seal lock agents harden slowly. You may have to wait for the seal lock adhesive to harden.
      Fig 2: Identifying Bolts Coated With Seal Lock Adhesive

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4. GASKETS
   1. When necessary, use a sealer on gaskets to prevent leaks.
5. BOLTS, NUTS AND SCREWS
   1. Carefully follow all the specifications for tightening torques. Always use a torque wrench.
6. FUSES
   1. When inspecting a fuse, check that the wire of the fuse is not broken.
   2. When replacing fuses, be sure that the new fuse has the correct amperage rating. Do not exceed the rating or use one with a lower rating.
      Fig 3: Identifying Fuses Condition

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      FUSE CHART
      
      

      Illustration	Symbol	Part	Name Abbreviation
      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002	Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002	FUSE	FUSE
      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002	Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002	MEDIUM CURRENT FUSE	M-FUSE
      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002	Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002	HIGH CURRENT FUSE	H-FUSE
      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002	Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002	FUSIBLE LINK	FL
      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002	Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002	CIRCUIT BREAKER	CB

7. CLIPS
   1. The removal and installation methods of typical clips used for vehicle body parts are shown in the table below.

      HINT:

      If clips are damaged during work, always replace the damaged clip with a new one.

      Fig 4: Identifying Clip Removal And Installation Process (1 Of 2)

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8. REMOVAL AND INSTALLATION OF VACUUM HOSES
   1. To disconnect a vacuum hose, pull and twist from the end of the hose. Do not pull from the middle of the hose as this may cause damage.
      Fig 5: Precaution For Disconnecting Vacuum Hose

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   2. When disconnecting vacuum hoses, use tags to identify where they should be reconnected.
   3. After completing any hose related repairs, double check that the vacuum hoses are properly connected. The label under the hood shows the proper layout.
   4. When using a vacuum gauge, never force the hose onto a connector that is too large. If a hose has been stretched, it may leak air. Use a step-down adapter if necessary.
      Fig 6: Disconnecting And Tagging Vacuum Hoses

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9. TORQUE WHEN USING TORQUE WRENCH WITH EXTENSION TOOL
   Fig 7: Identifying Torque Wrench With Extension Tool(1 Of 2)

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   1. Use the formula below to calculate special torque values for situations where SST or an extension tool is combined with the torque wrench.

      Formula: T' = L2/(L1 + L2) * T 

      FORMULAE CHART
      
      

      T'	Reading of torque wrench {N*m (kgf*cm, ft.*lbf)}
      T	Torque {N*m (kgf*cm, ft.*lbf)}
      L1	Length of SST or extension tool {cm (in.)}
      L2	Length of torque wrench {cm (in.)}

      Fig 8: Identifying Torque Wrench With Extension Tool(2 Of 2)

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      NOTE: If an extension tool or SST is combined with a torque wrench and the wrench is used to tighten to a torque specification in this information, the actual torque will be excessive and parts will be damaged.

The SIENNA is equipped with a Supplemental Restraint System (SRS).

1. GENERAL NOTICE
   1. As malfunctions of the SRS are difficult to confirm, the Diagnostic Trouble Codes (DTCs) become the most important source of information when troubleshooting. When troubleshooting the SRS, always check the DTCs before disconnecting the battery.
   2. Work must be started at least 90 seconds after the ignition switch is turned off and after the cable is disconnected from the negative (-) battery terminal.

      The SRS is equipped with a back-up power source. If work is started within 90 seconds after turning the ignition switch off and disconnecting the cable from the negative (-) battery terminal, the SRS may deploy.

      When the cable is disconnected from the negative (-) battery terminal, clock and audio system memory is erased. Before starting work, make a note of the settings of each memory system. When work is finished, reset the clock and audio system as before.

      CAUTION: Never use a back-up power source (battery or other) to avoid erasing system memory. The back-up power source may inadvertently power the SRS and cause it to deploy.
   3. In minor collisions where the SRS does not deploy, the steering pad, front passenger airbag assembly front seat side airbag assembly, curtain shield airbag assembly and front seat outer belt assembly should be inspected before further use of the vehicle.

      (See INSTALLATION for steering pad) (See INSTALLATION for front passenger airbag assembly)

      (See FRONT SEAT SIDE AIRBAG ASSEMBLY )

      (See CURTAIN SHIELD AIRBAG ASSEMBLY )

      (See FRONT SEAT OUTER BELT ASSEMBLY )

   4. Never use SRS parts from another vehicle. When replacing parts, use new parts.
   5. Before repairs, remove the airbag sensor assemblies if impacts are likely to be applied to the sensor during repairs.
   6. Never disassemble and attempt to repair all airbag sensor assemblies and all airbag assemblies.
      1. Steering pad
      2. Front passenger airbag assembly
      3. Front seat side airbag assembly
      4. Curtain shield airbag assembly
      5. Front seat outer belt assembly
   7. Replace the airbag sensor assemblies and the airbag assemblies if: 1) damage has occurred from being dropped, or 2) cracks, dents or other defects in the case, bracket or connector are present.
   8. Do not directly expose the airbag sensor assembly or airbag assembly to hot air or flames.
   9. Use a voltmeter / ohmmeter with high impedance (minimum=10 kΩ) for troubleshooting electrical circuits.
   10. Information labels are attached to the SRS components. Follow the instructions on the labels.
   11. After work on the SRS is completed, check the SRS warning light.
2. SPIRAL CABLE
   1. The steering wheel must be fitted correctly to the steering column with the spiral cable at the neutral position, as cable disconnection and other problems may occur. Refer to the information about correct installation of the steering wheel (See INSTALLATION ).
3. STEERING PAD
   1. Always place a removed or new steering pad surface upward as shown in the illustration. Placing the horn button with the pad surface facing down could cause a serious accident if the airbag inflates. Also, do not place anything on top of the horn button.
      Fig 9: Locating Marks

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      Fig 10: Identifying Steering Pad Surface Placing Posture

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   2. Never measure the resistance of the airbag squib. This may cause the airbag to inflate, which could cause serious injury.
      Fig 11: Identifying Precautions For Handling Airbag

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   3. Grease or detergents of any kind should not be applied to the horn button.
   4. Store the horn button assembly in an area where the ambient temperature is below 93°C (200°F), the humidity is not high and there is no electrical noise.
   5. When using electric welding anywhere on the vehicle, disconnect the airbag ECU connectors (4 pins). These connectors contain shorting springs. This feature reduces the possibility of the airbag deploying due to current entering the squib wiring.
   6. When disposing of the vehicle or the horn button assembly by itself, the airbag should be deployed using SST before DISPOSAL ). Activate the airbag in a safe place away from electrical noise.
4. FRONT PASSENGER AIRBAG ASSEMBLY
   1. Always place a removed or new front passenger airbag assembly with the pad surface facing upward as shown in the illustration. Placing the airbag assembly with the airbag inflation direction facing down could cause a serious accident if the airbag inflates.
      Fig 12: Identifying Correct Installation Procedure For Front Passenger Airbag Assembly

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   2. Never measure the resistance of the airbag squib. This may cause the airbag to inflate, which could cause serious injury.
      Fig 13: Identifying Airbag Handling Precautions Example (1 Of 2)

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   3. Grease or detergents of any kind should not be applied to the front passenger airbag assembly.
   4. Store the airbag assembly in an area where the ambient temperature is below 93°C (200°F), the humidity is not high and there is no electrical noise.
   5. When using electric welding anywhere on the vehicle, disconnect the airbag ECU connectors (4 pins). These connectors contain shorting springs. This feature reduces the possibility of the airbag deploying due to current entering the squib wiring.
   6. When disposing of the vehicle or the airbag assembly unit by itself, the airbag should be deployed using SST before DISPOSAL . Activate in a safe place, away from electrical noise.
5. FRONT SEAT SIDE AIRBAG ASSEMBLY
   1. Always place a removed or new front seat airbag assembly with the airbag inflation direction facing upward. Placing the airbag assembly with the airbag inflation direction facing downward could cause a serious accident if the airbag deploys.
   2. Never measure the resistance of the airbag squib (This may cause the airbag to inflate, which is very dangerous).
   3. Grease should not be applied to the front seat airbag assembly, and the airbag door should not be cleaned with detergents of any kind.
   4. Store the airbag assembly where the ambient temperature remains below 93°C (200°F), without high humidity and away from electrical noise.
   5. When using electric welding, disconnect the airbag connector (2 yellow pins) installed on the assembly before starting work.
   6. When disposing of a vehicle or the airbag assembly unit, the airbag should be deployed using SST before DISPOSAL . Activate in a safe place away from electrical noise. Example:
      Fig 14: Identifying Airbag Handling Precautions Example (2 Of 2)

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6. CURTAIN SHIELD AIRBAG ASSEMBLY
   1. Always place the removed or new curtain shield airbag assembly in a clear plastic bag, and keep it in a safe place.
      Fig 15: Placing Curtain Shield Airbag Assembly In Clear Plastic Bag

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      NOTE: Protective bag is not re-useable.
      CAUTION: Never disassemble the curtain shield airbag assembly.
   2. Never measure the resistance of the airbag squib (This may cause the airbag to inflate, which is very dangerous).
      Fig 16: Identifying Airbag Handling Precautions Example

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   3. Grease should not be attached to the curtain shield airbag assembly, and the surface should not be cleared with detergents of any kind.
   4. Store the airbag assembly where the ambient temperature remains below 93°C (200°F), without high humidity and away from electrical noise.
   5. When using electric welding, disconnect the airbag connector (2 yellow pins) into the instrument panel before starting work.
   6. When disposing of a vehicle or the curtain shield airbag assembly unit, the airbag should be deployed using SST before DISPOSAL .

      Activate in a safe place away from electrical noise.

7. FRONT SEAT OUTER BELT ASSEMBLY (SEAT BELT PRETENSIONER)
   1. Never measure the resistance of the seat outer belt. This may cause the pretensioner of the seat belt to activate, which could cause serious injury.
      Fig 17: Measuring Resistance Of Seat Outer Belt

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   2. Never disassemble the seat outer belt.
   3. Never install the seat outer belt on another vehicle.
   4. Store the seat outer belt in an area where the ambient temperature is below 80°C (176°F), the humidity is not high and there is no electrical noise.
   5. When using electric welding anywhere on the vehicle, disconnect the airbag ECU connectors (2 pins). These connectors contain shorting springs. This feature reduces the possibility of the airbag deploying due to current entering the squib wiring.
   6. When disposing of a vehicle or the seat outer belt unit by itself, the seat outer belt should be activated before DISPOSAL . Activate in a safe place away from electrical noise.
   7. As the seat outer belt is hot after being activated, allow some time for it to cool down sufficiently before disposal. Never apply water to cool down the seat outer belt.
   8. Grease, detergents, oil or water should not be applied to the front seat outer belt.
8. AIRBAG SENSOR ASSEMBLY
   1. Never reuse an airbag sensor assembly that has been involved in a collision where the SRS has deployed.
   2. The connectors to the airbag sensor assembly should be connected or disconnected with the sensor placed on the floor. If the connectors are connected or disconnected while the airbag sensor assembly is not placed on the floor, the SRS may activate.
   3. Work must be started at least 90 seconds after the ignition switch is turned off and the cable is disconnected from the negative (-) battery terminal, even if only loosening the set bolts of the airbag sensor assembly.
9. WIRE HARNESS AND CONNECTOR
   1. The SRS wire harness is integrated with the instrument panel wire harness assembly. All the connectors in the system are a standard yellow color. If the SRS wire harness becomes disconnected or the connector becomes broken, repair or replace it.

1. REMOVAL AND INSTALLATION OF BATTERY TERMINAL
   NOTE: Certain systems need to be initialized after disconnecting and reconnecting the cable from the negative (-) battery terminal.
   1. Before performing electronic work, disconnect the cable from the negative (-) battery terminal to prevent component and wire damage caused by accidental short circuits.
      Fig 18: Disconnecting Cable From Negative (-) Battery Terminal

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   2. When disconnecting the cable, turn the ignition switch and headlight dimmer switch off and loosen the cable nut completely. Perform these operations without twisting or prying the cable. Then disconnect the cable.
   3. Clock settings, radio settings, audio system memory, DTCs and other data are erased when the cable is disconnected from the negative (-) battery terminal. Write down any necessary data before disconnecting the cable.
2. HANDLING OF ELECTRONIC PARTS
   1. Do not open the cover or case of the ECU unless absolutely necessary. If the IC terminals are touched, the IC may be rendered inoperative by static electricity.
   2. Do not pull the wires when disconnecting electronic connectors. Pull the connector itself.
   3. Do not drop electronic components, such as sensors or relays. If they are dropped on a hard surface, they should be replaced.
   4. When cleaning the engine with steam, protect the electronic components, air filter and emission-related components from water.
   5. Never use an impact wrench to remove or install temperature switches or temperature sensors.
   6. When measuring the resistance between terminals of a wire connector, insert the tester probe carefully to prevent terminals from bending.
      Fig 19: Identifying Precautions While Handling Electrical Parts

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1. PLACE FOR REMOVING AND INSTALLING FUEL SYSTEM PARTS
   1. Work in a location with good air ventilation that does not have welders, grinders, drills, electric motors, stoves, or any other ignition sources.
   2. Never work in a pit or near a pit as vaporized fuel will collect in those places.
2. REMOVING AND INSTALLING FUEL SYSTEM PARTS
   1. Prepare a fire extinguisher before starting the operation.
   2. To prevent static electricity, install a ground wire to the fuel changer, vehicle and fuel tank, do not spray the surrounding area with water. Be careful when performing work in this area, as the work surface will become slippery. Do not clean up gasoline spills with water, as this may cause the gasoline to spread, and possibly create a fire hazard.
   3. Avoid using electric motors, working lights and other electric equipments that can cause sparks or high temperatures.
   4. Avoid using iron hammers as they may create sparks.
   5. Dispose of fuel-contaminated cloth separately using a fire resistant container.

1. If any metal particles enter inlet system parts, this may damage the engine.
2. When removing and installing inlet system parts, cover the openings of the removed parts and engine openings. Use gummed tape or other suitable materials.
3. When installing inlet system parts, check that no metal particles have entered the engine or the installed parts.
   Fig 20: Covering Openings

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1. Before removing the hose, check the clamp position so that it can be reinstalled in the same position.
2. Replace any deformed or dented clamps with new ones.
3. When reusing a hose, attach the clamp on the clamp track portion of the hose.
4. For a spring type clamp, you may want to spread the tabs slightly after installation by pushing in the direction of the arrows as shown in the illustration.
   Fig 21: Identifying Hose Clamp Installation Procedure

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1. Install the antenna far away from the ECU and sensors of the vehicle electronic systems as possible.
2. Install an antenna feeder at least 20 cm (7.87 in.) away from the ECU and sensors of the vehicle electronic systems. For details about ECU and sensors locations, refer to the article on the applicable components.
   Fig 22: Identifying Mobile Communication Systems Installation Precautions

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3. Keep the antenna and feeder separate from other wirings as much as possible. This will prevent signals sent from the communication equipment from affecting vehicle equipment and vice-versa.
4. Check that the antenna and feeder are correctly adjusted.
5. Do not install any high-powered mobile communication system.

The full-time 4WD SIENNA is equipped with the open center differential system.

If incorrect preparations or test procedures are used, the test will not only be unsuccessful, but may be dangerous as well.

Therefore, before beginning any such servicing or test, be sure to check the following items:

• Whether wheels should be touching ground or jacked up
• Transaxle gear position
• Maximum testing vehicle speed
• Maximum testing time

1. Before Beginning Test

   This vehicle does not have a center diff. lock mode or 4WD (Normal) Mode to allow only the front or rear wheel to be rotated.

   The test method for this vehicle is different from that for vehicles equipped with the center diff. lock mode or 4WD (Normal) Mode, so make sure to use the correct test method.

2. Braking Force Test

   (Vehicle Speed: Below 0.5 km/h or 0.3 mph)

   When performing low-speed type brake tester measurements, observe the following instructions.

   1. Position the wheels to be tested (front or rear) on the tester.
   2. Shift the transaxle shift lever to "N" position.
   3. Idle the engine, operate the brake booster and perform the test.
      Fig 23: Identifying Braking Force Test Procedures

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3. Speedometer Test or Other Tests (Using Speedometer Tester or Chassis Dynamometer)

   When performing test at high speed or high load, use the methods shown below.

   Fig 24: Identifying High Speed Or High Load Tests

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   NOTE:

   • Confirm that the vehicle is securely immobilized.
   • Never operate the brakes to drive the wheels or stop them suddenly.
4. On-Vehicle Wheel Balancing

   When doing on-vehicle wheel balancing on a full-time 4WD vehicle, to prevent the wheels from rotating at different speeds in different directions from each other (which could damage the center differential), always be sure to observe the following precautions:

   1. All 4 wheels should be jacked up, clearing the ground completely.
   2. The parking brake lever should be fully released.
   3. None of the brakes should be allowed to drag.
   4. The wheels should be driven on the wheel balancer with the engine running.

      HINT:

      When doing this, be careful of the other wheels, which will rotate at the same time.

   5. Avoid sudden acceleration, deceleration and braking.
   6. Carry out wheel balancing with the transaxle in D position.
      Fig 25: Identifying On-Vehicle Wheel Balancing Test Procedures

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When using a 2-wheel drum tester such as a speedometer tester or chassis dynamometer, etc., or jacking up the front wheels and driving the wheels, always push in the TRAC cut ("TRAC OFF") switch and turn the TRAC system OFF.

1. Confirm TRAC system is OFF
   1. Press the TRAC cut ("TRAC OFF") switch.
   2. Check that the TRAC OFF indicator light comes on when the TRAC system is turned OFF by the TRAC cut switch.
      Fig 26: Locating TRAC Off Switch And Indicator Light

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      HINT:

      The SLIP indicator light should always operate right after the engine is restarted.

   3. Begin measurements.
   4. Press the TRAC cut switch to turn the TRAC to the operative mode and check that the TRAC OFF indicator light goes off.

      HINT:

      The SLIP indicator light blinks when the TRAC system in operating.

      Fig 27: Identifying Slip Indicator Light Location

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1. Notices when using drum tester
   1. When using a drum tester, be sure to start the engine with the ignition switch OFF, and connect SST to the terminals TS and CG of the DLC3 before the measurement in order to cancel the VSC operation.

      SST 09843-18040 

      NOTE:

      • Confirm that the VSC warning light blinks.
      • The VSC system is reset when the engine is restarted.
      • Fasten the vehicle with lock chains.
        Fig 28: Locating DLC3 Connector Terminals

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2. Notice of related operations to VSC
   1. Do not carry out unnecessary installation and removal as it might disorder the adjustment of the parts related to the VSC.
   2. Be sure to carry out the preparation for operation and the confirmation of operation completion in accordance with the instructions of the text and when the operations related to the VSC are performed.

• Use one of the methods shown below to tow the vehicle.
• If the vehicle has trouble with the chassis or drive train, use method 1 (flat bed truck).
  Fig 29: Identifying Vehicle Towing Methods And Conditions

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  NOTE: Do not use any towing method other than those shown above.
• The towing methods shown below are dangerous and can damage the vehicle, so do not use them.
  Fig 30: Identifying Precautions While Towing Vehicle

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1. Use only unleaded gasoline.
2. Avoid idling the engine for more than 20 minutes.
3. Avoid performing unnecessary spark jump tests.
   1. Perform a spark jump test only when absolutely necessary. Perform this test as rapidly as possible.
   2. While testing, never race the engine.
4. Avoid a prolonged engine compression measurement. Engine compression measurements must be performed as rapidly as possible.
5. Do not run the engine when the fuel tank is nearly empty. This may cause the engine to misfire and create an extra load on the converter.