Avalon, Camry, Camry Solara, Highlander & Sienna

WARNING: This page does not describe the selected car, but rather 10 other vehicles, including the 2003 Toyota Tundra, 2003 Toyota Tacoma, 2003 Toyota Sienna, 2003 Toyota Sequoia, and 2003 Toyota Land Cruiser. However, it is still accessible from the selected car via links, so may be relevant.

Remove "V" bank cover located on top of engine. See Fig 1-Fig 5 .
Disconnect electrical connector and vacuum hoses from intake air control valve Vacuum Switching Valve (VSV). See Fig 1-Fig 5 . On Avalon, Camry (Jan. 2003 and later production models), Highlander and Sienna, 2 intake air control valve VSVs are used. Intake air control valve No. 1 VSV is for intake air control valve near throttle bodies which may also be referred to as No. 1 intake air control valve. Intake air control valve No. 2 VSV is for intake air control valve on end of air intake chamber which may also be referred to as No. 2 intake air control valve. On all models, it may be necessary to remove emission control valve set which contains various vacuum switching valves for access to intake air control valve VSV.
Using ohmmeter, check that continuity exists between electrical terminals on intake air control valve VSV and that resistance is 33-39 ohms at 68°F (20°C). If continuity exists and resistance is within specification, go to next step. If no continuity exists or resistance is not within specification, replace intake air control valve VSV.
Using ohmmeter, ensure no continuity exists between each electrical terminal and body of intake air control valve VSV. If continuity does not exist between electrical terminal and body of intake air control valve VSV, go to next step. If continuity exists between electrical terminal and body of intake air control valve VSV, replace intake air control valve VSV.
Apply air pressure to port "B" on intake air control valve VSV. Ensure air flows from the filter and not from port "A". Perform STEP 1 in illustration. See Fig 6.
Apply battery voltage and ground to electrical terminals on intake air control valve VSV. Apply air pressure to port "B" on intake air control valve VSV. Ensure air flows from port "A" and not from the filter. Perform STEP 2 in illustration. See Fig 6. If intake air control valve VSV operates properly, reinstall intake air control valve VSV and go to next step. If intake air control valve VSV does not operate properly, replace intake air control valve VSV and recheck system operation.
On Avalon, Camry, Camry Solara and Highlander, remove glove box for access to Engine Control Module (ECM). On Sienna, remove passenger's side lower instrument panel cover for access to Engine Control Module (ECM). On all models, for illustration of ECM location, see ENGINE CONTROL MODULE under COMPONENT LOCATIONS. Note ECM electrical connector terminal identification. See Figure - Figure and Figure .
Turn ignition on. Using voltmeter, check voltage between body ground and specified ECM terminal(s). See ECM TERMINAL IDENTIFICATION FOR INTAKE AIR CONTROL VALVE VSV table. This is the wire from intake air control valve VSV to ECM. Intake air control valve VSV may also be referred to as ACIS VSV. Voltage should be 9-14 volts.
If voltage is within specification, go to next step. If voltage is not within specification, check for open and short in wiring harness and connectors between EFI main relay, intake air control valve VSV and ECM. EFI main relay is located in fuse/relay box at driver's side front corner of engine compartment and may also be referred to as EFI relay. See appropriate WIRING DIAGRAM under ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS.
On Avalon, Camry Solara and Sienna, go to next step. On Camry and Highlander, go to step 14.
Disconnect hoses from vacuum tank. Vacuum tank is located near driver's side front corner of engine compartment, below battery tray. Apply air pressure to port "B" on vacuum tank. Ensure air flows from port "A". Perform STEP 1 in illustration. See Fig 7.
Apply air pressure to port "A". Ensure air does not flow from port "B". Perform STEP 2 in illustration. See Fig 7.
Plug port "B". Using vacuum pump, apply 7.9 in. Hg of vacuum to port "A". Perform STEP 3 in illustration. See Fig 7. Ensure vacuum reading will hold for at least one minute. If vacuum tank is okay, reconnect vacuum hoses and go to step 16. If vacuum tank is defective, replace vacuum tank and recheck system operation.
Disconnect hoses from vacuum tank. Vacuum tank is located on upper cap on air cleaner assembly. See Fig 2, Fig 3 and Fig 5 . Note ports on vacuum tank. See Fig 8. Plug port "C" on vacuum tank. Apply air pressure to port "B". Ensure air flows from port "A".
Plug port "C". Apply air pressure to port "A". Ensure air does not flow from port "B". Plug ports "A" and "C". On Camry, using vacuum pump, apply 18 in. Hg of vacuum to port "B". On Highlander, using vacuum pump, apply 24 in. Hg of vacuum to port "B". On all models, ensure vacuum reading will hold for at least one minute. If vacuum tank is okay, reconnect vacuum hoses and go to next step. If vacuum tank is defective, replace vacuum tank or upper cap on air cleaner assembly as necessary and recheck system operation.
On all models, check ECM ground circuit. See ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS article in ELECTRICAL. If ECM ground circuit is okay, replace ECM. If ECM is replaced and vehicle is equipped with engine immobilizer system, ECM must be programmed with proper ignition key code for engine immobilizer system. Models equipped with engine immobilizer system may be identified by looking at the ignition key. On models equipped with engine immobilizer system, the top of the ignition key is thicker than a standard ignition key, as a transponder chip is incorporated into the top of the ignition key. For programming procedures, see COMPUTER RELEARN PROCEDURES - TOYOTA article in GENERAL INFORMATION, or appropriate ENGINE IMMOBILIZER SYSTEMS article in ACCESSORIES & EQUIPMENT.

Fig 1: Locating "V" Bank Cover & Various Vacuum Switching Valves (Avalon & Sienna)