Introduction: Other Toyota Sequoia I

ENGINE SERIAL NUMBER

The engine serial number is stamped on the engine block. (Scheme 44)

Scheme 44

Scheme 45

Scheme 46

Scheme 47

Scheme 48

Scheme 49

1. Use fender, seat and floor covers to keep the vehicle clean and prevent damage.
2. During disassembly, keep parts in the appropriate order to facilitate reassembly.
3. Installation and removal of battery terminal Before performing electrical work, disconnect the negative (-) terminal cable from the battery. If it is necessary to disconnect the battery for inspection or repair, first disconnect the negative (-) terminal cable. When disconnecting the terminal cable, to prevent damage to battery terminal, loosen the cable nut and raise the cable straight up without twisting or prying it. Clean the battery terminals and cable ends with a clean shop rag. Do not scrape them with a file or other abrasive objects Install the cable ends to the battery terminals after loosening the nut and tighten the nut after installation. Do not use a hammer to tap the cable ends onto the terminals. Be sure the cover for the positive (+) terminal is properly in place.
4. Check hose and wiring connectors to make sure that they are connected securely and correctly.
5. Non-reusable parts Always replace cotter pins, gaskets, O-rings, oil seals; etc. with new ones. Non-reusable parts are indicated in component illustrations.
6. Precoated parts are bolts, nuts, etc. that are coated with a seal lock adhesive at the factory (Scheme 45) If a precoated part is retightened, loosened or caused to move in any way, it must be recoated with the specified adhesive. When reusing precoated parts, clean off the old adhesive and dry with compressed air. Then apply the specified seal lock adhesive to the bolt, nut or threads. Precoated parts are indicated in the component illustrations.
7. When necessary, use a sealer on gaskets to prevent leaks.
8. Carefully observe all specifications for bolt tightening torques. Always use a torque wrench.
9. Use of special service tools (SST) and special service materials (SSM) may be required, depending on the nature of the repair. Be sure to use SST and SSM where specified and follow the proper work procedure.
10. When replacing fuses, be sure the new fuse has the correct amperage rating. DO NOT exceed the rating or use one with a lower rating.
11. Care must be taken when jacking up and supporting the vehicle. Be sure to lift and support the vehicle at the proper locations. See «VEHICLE LIFT AND SUPPORT LOCATIONS»(ref-174490-S19340549332005040500000). Release parking brake on a level surface and shift the transmission in Neutral (or N position). When jacking up the front wheels, first place stoppers behind the rear wheels. When jacking up the rear wheels, first place stoppers before the front wheels. When either the front or rear wheels only should be jacked up, set rigid racks and place stoppers in front and behind the other wheels on the ground. After the vehicle is jacked up, be sure to support it on rigid racks. It is extremely dangerous to do any work on a vehicle raised on a jack alone, even for a small job that can be finished quickly.
12. Observe the following precautions to avoid damage to the following parts: Do not open the cover or case of the ECU unless absolutely necessary. If the IC terminals are touched, the IC may be destroyed by static electricity. To disconnect vacuum hoses, pull off the end, not the middle of the hose. (Scheme 48) To pull apart electrical connectors, pull on the connector itself, not the wires. Be careful not to drop electrical components, such as sensors or relays. If they are dropped on a hard floor, they should be replaced and not reused. When steam cleaning an engine, protect the electronic components, air filter and emission-related components from water. Never use an impact wrench to remove or install temperature switches or temperature sensors. When checking continuity at the wire connector, insert the tester probe carefully to prevent terminals from bending. When using a vacuum gauge, never force the hose onto a connector that is too large. Use a step-down adapter for adjustment. Once the hose has been stretched, it may leak air.
13. Installation and removal of vacuum hose: When disconnecting vacuum hoses, use tags to identify where they should be reconnected to. see scheme 9 After completing a job, double check that the vacuum hoses are properly connected. A label under the hood shows the proper layout.
14. Bleeding of hydraulic brake booster: When repairing the hydraulic brake booster or ABS, TRAC and VSC system, bleed the air out of the hydraulic brake system. See «BLEEDING BRAKE SYSTEM»(ref-162458-S22400929732004060200000).
15. Unless otherwise stated, all resistance is measured at an ambient temperature of 20°C (68°F). Because the resistance may be outside specifications if measured at high temperatures immediately after the vehicle has been running, measurement should be made when the engine has cooled down.

FOR VEHICLES EQUIPPED WITH CONTROL (VSC) SYSTEM

Scheme 50

Scheme 51

1. Confirm VSC System Is Off Turn the ignition switch OFF. Using SST, connect terminals Ts and E1 of DLC3. SST 09843-18020. Start the engine. Check that the VSC TRAC warning light blinks. After the measurement, remove the SST and restart the engine. At this time make sure that the VSC TRAC warning light is off.
2. Notice For VSC Operation Remove and reinstall of VSC-related components may misadjusted them. Do not remove or reinstall them without necessary When conducting VSC-related operations, do not fail to make sure that the preparation and the finishing of the operation are all performed in accordance with the direction in this text.

FOR VEHICLES EQUIPPED WITH A CATALYTIC CONVERTER

IF VEHICLE IS EQUIPPED WITH MOBILE COMMUNICATION SYSTEM

For vehicles with mobile communication systems such as two-way radios and cellular telephones, observe the following precautions

1. Install the antenna as far as possible away from the ECU and sensors of the vehicle's electronic system.
2. Install the antenna feeder at least 20 cm (7.87 in.) away from the ECU and sensors of the vehicle's electronic systems. For details about ECU and sensors locations, refer to the section on the applicable component.
3. Avoid winding the antenna feeder together with other wiring as much as possible, and also avoid running the antenna feeder parallel with other wire harness.
4. Check that the antenna and feeder are correctly adjusted.
5. Do not install powerful mobile communications system.

FOR USING OBD II SCANTOOL OR TOYOTA HAND-HELD TESTER

Observe the following for safety reasons

1. Before using the OBD II SCANTOOL or TOYOTA hand-held tester, the OBD II scan tool's instruction book or TOYOTA hand-held tester's operator manual should be read thoroughly.
2. Be sure to route all cables securely when driving with the OBD II scan tool or TOYOTA hand- held tester connected to the vehicle. (i.e. Keep cables away from feet, pedals, steering wheel and shift lever).
3. Two persons are required when test driving with the OBD II scan tool or TOYOTA hand-held tester, one person to drive the vehicle and one person to operate the OBD II scan tool or TOYOTA hand-held tester.

Customer Problem Analysis

In troubleshooting, the problem symptoms must be confirmed accurately and all preconceptions must be cleared away in order to give an accurate judgment. To ascertain just what the problem symptoms are, it is extremely important to ask the customer about the problem and the conditions at the time it occurred.

Important Points in the Problem Analysis

The following 5 items are important points in the problem analysis. Past problems which are thought to be unrelated and the repair history, etc. may also help in some cases, so as much information as possible should be gathered and its relationship with the problem symptoms should be correctly ascertained for reference in troubleshooting. A customer problem analysis table is provided in most articles for each system for your use.

1. What: vehicle model, system name.
2. When: date, time, occurrence frequency.
3. Where: road conditions.
4. Under what conditions? Running conditions, driving conditions, weather conditions.
5. How did it happen? Problem symptoms

Scheme 52