Engine Control System & Component Testing - 4-CYLINDER: Diagnosis Toyota Echo I

Fuel EVAP System Test (Camry & Highlander)

Note. Manufacturer provides testing information for testing airtightness of fuel tank and components along with testing of charcoal canister and fuel EVAP system.

Scheme 85

Scheme 86

Scheme 87

1. Inspect all fuel EVAP system lines and connections for sharp bends or damage. Fuel inlet pipe may also be referred to as fuel filler pipe. Inspect fuel inlet pipe for cracks, damage or fuel leakage. Inspect fuel tank cap for cracks or deformed gasket. Replace components if defective or damaged.
2. Start engine and warm engine to normal operating temperature. Shut engine off. Connect vacuum gauge from EVAP System Test Kit (00002-6872A) to EVAP service port. EVAP service port is located in engine compartment, in purge vacuum hose for EVAP system, near air cleaner assembly. EVAP service port contains a Green label for identification.
3. Operate EVAP Vacuum Switching Valve (VSV). If Toyota hand-held tester is available to operate EVAP VSV, go to next step. If Toyota hand-held tester is not available to operate EVAP VSV, go to step 5.
4. Connect hand-held tester to data link connector No. 3 at driver's side of instrument panel. see scheme 8and see scheme 13.. Start engine. Turn hand-held tester on. Select ACTIVE TEST MODE on hand-held tester. Using hand-held tester manufacturer's instructions, activate EVAP VSV. Go to step 6.
5. Disconnect electrical connector at EVAP VSV. On Camry, EVAP VSV is located near rear of air cleaner housing and contains Blue or Black 2-pin electrical connector with Black/White and Black/Red wires. On Highlander, EVAP VSV is located on rear of air cleaner housing and contains Blue 2-pin electrical connector with Black/White and Black/Red wires. On all models, using jumper wires, connect battery voltage and ground to electrical terminals on EVAP VSV to operate EVAP VSV. Start engine. Go to next step.
6. Check vacuum reading on vacuum gauge with engine idling. Vacuum reading should be.368-19.713 in. Hg (5.00-268.00 in. H2O) for over 5 seconds. If vacuum reading is within specification, go to next step. If vacuum reading is not within specification, check for loose or restricted vacuum hose to EVAP service port, or for malfunctioning EVAP VSV. To check EVAP VSV operation, see «EVAP VACUUM SWITCHING VALVE»(ref-133221-S30853527182002021900000).
7. Shut engine off. If using hand-held tester to operate EVAP VSV, stop operation of EVAP VSV. Remove hand-held tester. Go to next step. If connecting battery voltage to EVAP VSV to operate EVAP VSV, disconnect jumper wires and reconnect electrical connector on EVAP VSV. Go to next step.
8. Disconnect vacuum gauge from EVAP service port. Connect pressure gauge to EVAP service port. Install hose crimper on air drain hose near charcoal canister. Perform STEP 1 in illustration. (Scheme 86)and (Scheme 87). Charcoal canister is located near the fuel tank.
9. Apply 13.5-15.5 in. H2O of pressure to EVAP service port. After 2 minutes of applying pressure, pressure should be 7.7-8.8 in. H2O. If pressure is within specification, go to next step. If pressure cannot be maintained, remove hose crimper. Check for disconnected vacuum hose between EVAP VSV, charcoal canister and fuel tank. If vacuum hose is properly installed on EVAP VSV, charcoal canister and fuel tank, check for stuck open EVAP VSV. To check EVAP VSV operation, see «EVAP VACUUM SWITCHING VALVE»(ref-133221-S30853527182002021900000).
10. With pressure still applied at EVAP service port, remove fuel tank cap and note pressure reading. Pressure should decrease when fuel tank cap is removed. If pressure decreases when fuel tank cap is removed, remove pressure gauge and hose crimper. Go to next step. If pressure does not decrease when fuel tank cap is removed, remove pressure gauge and hose crimper. Check for restricted vacuum hose between EVAP service port, charcoal canister and fuel tank. Repair or replace vacuum hose as necessary.
11. To check airtightness of fuel tank and fuel inlet pipe, disconnect EVAP line hose from charcoal canister. Perform STEP 2 in illustration. (Scheme 86)and (Scheme 87). Apply.58 psi (.040 kg/cm 2 ) air pressure to EVAP line hose so pressure inside fuel tank is.58 psi (.040 kg/cm 2 ). Check that pressure inside fuel tank holds steady for one minute.
12. If pressure inside fuel tank holds steady for one minute, reinstall EVAP line hose on charcoal canister. Go to next step. If pressure inside fuel will not hold steady for one minute, check for leaking hoses or pipes at fuel tank and fuel inlet pipe, or for leaks at fuel tank or installed components on fuel tank. If no leaks exist, replace fuel tank and fuel inlet pipe. Reinstall EVAP line hose on charcoal canister. Go to next step.
13. To check overfill check valve and cut-off valve, disconnect purge line hose and EVAP line hose from charcoal canister and install cap on air drain hose. Perform STEP 3 in illustration. (Scheme 86)and (Scheme 87).
14. Apply.58 psi (.040 kg/cm 2 ) air pressure to purge line hose fitting on charcoal canister. Perform STEP 3 in illustration. (Scheme 86)and (Scheme 87). Ensure air flows from EVAP line hose when air pressure is applied to purge line hose fitting on charcoal canister. If fuel tank is full of fuel, air may not flow from EVAP line hose, as overfill check valve may be closed. Ensure fuel tank is not full of fuel when checking for airflow at EVAP line hose.
15. If air flows from EVAP line hose, go to next step. If air does not flow from EVAP line hose, check for restrictions in EVAP line hose and vent line hose. If any hose is restricted, replace hose and recheck operation. If hoses are not restricted, replace overfill check valve and cut-off valve located on top of fuel tank.
16. Reinstall purge line hose and EVAP line hose on charcoal canister. To check air inlet line, disconnect air inlet line hose from charcoal canister. Perform STEP 4 in illustration. (Scheme 86)and (Scheme 87). Apply air pressure to air inlet line hose. Air should flow through air inlet line hose. If air flows through air inlet line hose, go to next step. If air does not flow through air inlet line hose, check for restricted air inlet line hose or air inlet line.
17. To check charcoal canister, disconnect necessary electrical connectors and components for removal of charcoal canister. Remove retaining bolts/nuts and charcoal canister. Inspect charcoal canister for cracks or damage. If charcoal canister is okay, go to next step. If charcoal canister is defective, replace charcoal canister.
18. Install cap on vent port on charcoal canister. (Scheme 88) Apply.26 psi (.018 kg/cm 2 ) air pressure to EVAP port while holding purge port closed. (Scheme 88) Ensure air flows freely from air drain port.
19. Apply.26 psi (.018 kg/cm 2 ) air pressure to EVAP port while holding air drain port and purge port closed. (Scheme 88) Ensure air does not flow for air inlet port.
20. Using vacuum pump, apply 1.01 in. Hg of vacuum to purge port. (Scheme 88) Ensure vacuum does not decrease when air inlet port is closed and that vacuum decreases when air inlet port is opened.
21. While holding air inlet port closed, use vacuum pump to apply 1.01 in. Hg of vacuum to EVAP port. (Scheme 88) Ensure air flows into purge port. Remove cap from vent port. Replace charcoal canister if defective.
22. Reinstall charcoal canister. If fuel EVAP system operates properly, it may be necessary to check operation of EVAP VSV, canister closed valve Vacuum Switching Valve (VSV) and pressure switching valve Vacuum Switching Valve (VSV). See «EVAP VACUUM SWITCHING VALVE»(ref-133221-S30853527182002021900000), «CANISTER CLOSED VALVE VACUUM SWITCHING VALVE»(ref-133221-S07084902692002021900000) and «PRESSURE SWITCHING VALVE VACUUM SWITCHING VALVE»(ref-133221-S17724300352002021900000). Manufacturer does provide individual component testing for vapor pressure sensor. If problem exists with vapor pressure sensor, a Diagnostic Trouble Code (DTC) may be stored in Engine Control Module (ECM). See TESTING PROCEDURE under SELF-DIAGNOSTIC SYSTEM in appropriate SELF-DIAGNOSTICS article for retrieving of DTCs.

Fuel EVAP System Test (Camry Solara, Celica, Corolla, MR2, RAV4 & Tacoma)

Note. Manufacturer provides testing information for testing airtightness of fuel tank and components along with testing of charcoal canister and fuel EVAP system.

Scheme 88

Scheme 89

Scheme 90

Scheme 91

Scheme 92

Scheme 93

1. Inspect all fuel EVAP system lines and connections for sharp bends or damage. Fuel inlet pipe may also be referred to as fuel filler pipe. Inspect fuel inlet pipe for cracks, damage or fuel leakage. Inspect fuel tank cap for cracks or deformed gasket. Replace components if defective or damaged.
2. Start engine and warm engine to normal operating temperature. Shut engine off. Connect vacuum gauge from EVAP System Test Kit (00002-6872A) to EVAP service port. EVAP service port is located in engine compartment, in purge vacuum hose for EVAP system. see scheme 160- see scheme 162, see scheme 164, see scheme 166 and see scheme 167.
3. Operate EVAP Vacuum Switching Valve (VSV). If Toyota hand-held tester is available to operate EVAP VSV, go to next step. If Toyota hand-held tester is not available to operate EVAP VSV, go to step 5.
4. Connect hand-held tester to data link connector No. 3 at driver's side of instrument panel. see scheme 9- see scheme 11, see scheme 14 see scheme 16 and see scheme 17. Start engine. Turn hand-held tester on. Select ACTIVE TEST MODE on hand-held tester. Using hand-held tester manufacturer's instructions, activate EVAP VSV. Go to step 6.
5. Disconnect electrical connector at EVAP VSV. See «EVAP VSV LOCATION»(ref-133221-S01834189612002021900000) table. see scheme 160- see scheme 162, see scheme 164, see scheme 166 and see scheme 167. Using jumper wires, connect battery voltage and ground to electrical terminals on EVAP VSV to operate EVAP VSV. Start engine. Go to next step. EVAP VSV LOCATION Application Location Camry Solara On Air Intake Hose, Near Air Cleaner Assembly & Contains Black 2-Pin Electrical Connector With Black/White & Black/Red Wires Celica On Bracket At Rear Of Air Cleaner Housing & Contains Black 2-Pin Electrical Connector With Green/Orange & Black/White Wires Corolla On Bracket At Rear Of Air Cleaner Housing & Contains Black 2-Pin Electrical Connector With Blue/Black & Black Wires MR2 On Air Intake Hose, Near Air Cleaner Assembly & Contains Blue 2-Pin Electrical Connector With Black/Red & White Wires RAV4 On Air Intake Hose, Near Air Cleaner Assembly & Contains Black 2-Pin Electrical Connector With Black/Red & Pink Wires Tacoma On Bracket Bolted To Inside Of Driver's Side Front Fender Panel & Contains Black 2-Pin Electrical Connector With White/Green & White/Red Wires
6. Check vacuum reading on vacuum gauge with engine idling. Vacuum reading should be within specification for over 5 seconds. See «VACUUM SPECIFICATIONS»(ref-133221-S16108910942002021900000) table. If vacuum reading is within specification, go to next step. If vacuum reading is not within specification, check for loose or restricted vacuum hose to EVAP service port, or for malfunctioning EVAP VSV. To check EVAP VSV operation, see «EVAP VACUUM SWITCHING VALVE»(ref-133221-S30853527182002021900000). VACUUM SPECIFICATIONS Application In. Hg (In. H20) Camry Solara, Celica, Corolla & Tacoma.368-19.713 (5.00-268.00) MR2 & RAV4.368-3.678 (5.00-50.00)
7. Shut engine off. If using hand-held tester to operate EVAP VSV, stop operation of EVAP VSV. Remove hand-held tester. Go to next step. If connecting battery voltage to EVAP VSV to operate EVAP VSV, disconnect jumper wires and reconnect electrical connector on EVAP VSV. Go to next step.
8. Disconnect vacuum gauge from EVAP service port. Connect pressure gauge to EVAP service port. Install hose crimper on air drain hose near charcoal canister. Perform STEP 1 in illustration. (Scheme 86)and (Scheme 89) - (Scheme 92). On MR2, hose crimper should be installed at White-colored area on air drain hose. On RAV4, hose crimper should be installed at Yellow-colored area on air drain hose. On all models, charcoal canister is located near fuel tank. see scheme 160- see scheme 162, see scheme 164, see scheme 166 and see scheme 167.
9. Apply 13.5-15.5 in. H2O of pressure to EVAP service port. After 2 minutes of applying pressure, pressure should be 7.7-8.8 in. H2O. If pressure is within specification, go to next step. If pressure cannot be maintained, remove hose crimper. Check for disconnected vacuum hose between EVAP VSV, charcoal canister and fuel tank. If vacuum hose is properly installed on EVAP VSV, charcoal canister and fuel tank, check for stuck open EVAP VSV. To check EVAP VSV operation, see «EVAP VACUUM SWITCHING VALVE»(ref-133221-S30853527182002021900000).
10. With pressure still applied at EVAP service port, remove fuel tank cap and note pressure reading. Pressure should decrease when fuel tank cap is removed. If pressure decreases when fuel tank cap is removed, remove pressure gauge and hose crimper. Go to next step. If pressure does not decrease when fuel tank cap is removed, remove pressure gauge and hose crimper. Check for restricted vacuum hose between EVAP service port, charcoal canister and fuel tank. Repair or replace vacuum hose as necessary.
11. To check airtightness of fuel tank and fuel inlet pipe, disconnect EVAP line hose from charcoal canister. Perform STEP 2 in illustration. (Scheme 86)and (Scheme 89) - (Scheme 92). Apply.58 psi (.040 kg/cm 2 ) air pressure to EVAP line hose so pressure inside fuel tank is.58 psi (.040 kg/cm 2 ). Check that pressure inside fuel tank holds steady for one minute.
12. If pressure inside fuel tank holds steady for one minute, reinstall EVAP line hose on charcoal canister. Go to next step. If pressure inside fuel will not hold steady for one minute, check for leaking hoses or pipes at fuel tank and fuel inlet pipe, or for leaks at fuel tank or installed components on fuel tank. If no leaks exist, replace fuel tank and fuel inlet pipe. Reinstall EVAP line hose on charcoal canister. Go to next step.
13. To check overfill check valve and cut-off valve, disconnect purge line hose and EVAP line hose from charcoal canister. Install cap on air drain hose or cap on air drain hose fitting on charcoal canister. Perform STEP 3 in illustration. (Scheme 86)and (Scheme 89) - (Scheme 92).
14. Apply.58 psi (.040 kg/cm 2 ) air pressure to purge line hose fitting on charcoal canister. Perform STEP 3 in illustration. (Scheme 86)and (Scheme 89) - (Scheme 92). Ensure air flows from EVAP line hose when air pressure is applied to purge line hose fitting on charcoal canister. If fuel tank is full of fuel, air may not flow from EVAP line hose, as overfill check valve may be closed. Ensure fuel tank is not full of fuel when checking for airflow at EVAP line hose.
15. If air flows from EVAP line hose, go to next step. If air does not flow from EVAP line hose, check for restrictions in EVAP line hose and vent line hose. If any hose is restricted, replace hose and recheck operation. If hoses are not restricted, replace overfill check valve and cut-off valve (if equipped). Overfill check valve and cut-off valve (if equipped) are located on top of fuel tank. see scheme 160- see scheme 162, see scheme 164, see scheme 166 and see scheme 167.
16. Reinstall purge line hose and EVAP line hose on charcoal canister. To check air inlet line, disconnect air inlet line hose from charcoal canister. Perform STEP 4 in illustration. (Scheme 86)and (Scheme 89) - (Scheme 92). Apply air pressure to air inlet line hose. Air should flow through air inlet line hose. If air flows through air inlet line hose, go to next step. If air does not flow through air inlet line hose, check for restricted air inlet line hose or air inlet line.
17. To check charcoal canister, remove necessary components for access to charcoal canister. Disconnect necessary electrical connectors for removal of charcoal canister. Disconnect purge line hose, EVAP line hose and air inlet line hose from charcoal canister if not previously done.
18. Push connector on vent line hose toward charcoal canister and pinch both sides of retainer on connector, and then disconnect vent line hose with connector from charcoal canister. (Scheme 93)and (Scheme 94).
19. Remove vapor pressure sensor bolts/nut (if equipped). Remove retaining bolts/nuts and charcoal canister. Inspect charcoal canister for cracks or damage. If charcoal canister is okay, go to next step. If charcoal canister is defective, replace charcoal canister.
20. On Camry Solara, Celica, MR2 and RAV4 install cap on vent port on charcoal canister. (Scheme 88) On Corolla and Tacoma, install hose and cap on vent port. (Scheme 88) On all models, apply.26 psi (.018 kg/cm 2 ) air pressure to EVAP port while holding purge port closed. (Scheme 88) Ensure air flows freely from air drain port.
21. Apply.26 psi (.018 kg/cm 2 ) air pressure to EVAP port while holding air drain port and purge port closed. (Scheme 88) Ensure air does not flow from air inlet port.
22. Using vacuum pump, apply 1.01 in. Hg of vacuum to purge port. (Scheme 88) Ensure vacuum does not decrease when air inlet port is closed and that vacuum decreases when air inlet port is opened.
23. While holding air inlet port closed, use vacuum pump to apply 1.01 in. Hg of vacuum to EVAP port. (Scheme 88) Ensure air flows into purge port. Remove hose (if used) and cap from vent port. Replace charcoal canister if defective.
24. Reinstall charcoal canister. If fuel EVAP system operates properly, it may be necessary to check operation of EVAP VSV, canister closed valve Vacuum Switching Valve (VSV), pressure switching valve Vacuum Switching Valve (VSV) and vapor pressure sensor. See «EVAP VACUUM SWITCHING VALVE»(ref-133221-S30853527182002021900000), «CANISTER CLOSED VALVE VACUUM SWITCHING VALVE»(ref-133221-S07084902692002021900000), «PRESSURE SWITCHING VALVE VACUUM SWITCHING VALVE»(ref-133221-S17724300352002021900000) and appropriate «VAPOR PRESSURE SENSOR»(ref-133221-S31923657072002021900000) procedure.

Fuel EVAP System Test (ECHO)

Note. Manufacturer provides testing information for testing airtightness of fuel tank and components along with testing of charcoal canister and fuel EVAP system.

Scheme 94

Scheme 95

Scheme 96

1. Inspect all fuel EVAP system lines and connections for sharp bends or damage. Fuel inlet pipe may also be referred to as fuel filler pipe. Inspect fuel inlet pipe for cracks, damage or fuel leakage. Inspect fuel tank cap for cracks or deformed gasket. Replace components if defective or damaged.
2. Start engine and warm engine to normal operating temperature. Shut engine off. Connect vacuum gauge from EVAP System Test Kit (00002-6872A) to EVAP service port. EVAP service port is located in engine compartment, in purge vacuum hose for EVAP system. see scheme 163
3. Operate EVAP Vacuum Switching Valve (VSV). If Toyota hand-held tester is available to operate EVAP VSV, go to next step. If Toyota hand-held tester is not available to operate EVAP VSV, go to step 5.
4. Connect hand-held tester to data link connector No. 3 at driver's side of instrument panel. see scheme 12 Start engine. Turn hand-held tester on. Select ACTIVE TEST MODE on hand-held tester. Using hand-held tester manufacturer's instructions, activate EVAP VSV. Go to step 6.
5. Disconnect electrical connector at EVAP VSV. EVAP VSV is located on bracket at side of air cleaner housing and contains Blue 2-pin electrical connector with Black/Yellow and White/Green wires. see scheme 163 Using jumper wires, connect battery voltage and ground to electrical terminals on EVAP VSV to operate EVAP VSV. Start engine. Go to next step.
6. Check vacuum reading on vacuum gauge with engine idling. Vacuum reading should be.368-19.713 in. Hg (5.00-268.00 in. H2O) for over 5 seconds. If vacuum reading is within specification, go to next step. If vacuum reading is not within specification, check for loose or restricted vacuum hose to EVAP service port, or for malfunctioning EVAP VSV. To check EVAP VSV operation, see «EVAP VACUUM SWITCHING VALVE»(ref-133221-S30853527182002021900000).
7. Shut engine off. If using hand-held tester to operate EVAP VSV, stop operation of EVAP VSV. Leave hand-held tester connected to data link connector No. 3 and go to next step. If connecting battery voltage to EVAP VSV to operate EVAP VSV, disconnect jumper wires and reconnect electrical connector on EVAP VSV. Go to next step.
8. Disconnect vacuum gauge from EVAP service port. Connect pressure gauge to EVAP service port. Operate Canister Closed Valve Vacuum Switching Valve (CCV VSV). If Toyota hand-held tester is available to operate CCV VSV, go to next step. If Toyota hand-held tester is not available to operate CCV VSV, go to step 10.
9. With hand-held tester still connected to DLC No. 3, turn ignition on and then turn hand-held tester on. DO NOT start engine. Select ACTIVE TEST MODE on hand-held tester. Using hand-held tester manufacturer's instructions, activate CCV VSV. Go to step 11.
10. Install hose crimper on air drain hose near charcoal canister. Charcoal canister is located near fuel tank. see scheme 163 Perform STEP 1 in illustration. (Scheme 95) Go to next step.
11. Apply 13.5-15.5 in. H2O of pressure to EVAP service port. After 2 minutes of applying pressure, pressure should be 7.7-8.8 in. H2O. If pressure is within specification, go to next step. If pressure cannot be maintained, check for disconnected vacuum hose between EVAP VSV, charcoal canister and fuel tank. If vacuum hose is properly installed on EVAP VSV, charcoal canister and fuel tank, check for stuck open EVAP VSV. To check EVAP VSV operation, see «EVAP VACUUM SWITCHING VALVE»(ref-133221-S30853527182002021900000).
12. With pressure still applied at EVAP service port, remove fuel tank cap and note pressure reading. Pressure should decrease when fuel tank cap is removed. If pressure decreases when fuel tank cap is removed and hand-held tester was used to activate CCV VSV, turn ignition off. Remove pressure gauge and hand-held tester. Go to next step. If pressure decreases when fuel tank cap is removed and hand-held tester was not used to operate CCV VSV, remove hose crimper and pressure gauge. Go to next step. On all applications, if pressure does not decrease when fuel tank cap is removed, remove pressure gauge and hose crimper. Check for restricted vacuum hose between EVAP service port, charcoal canister and fuel tank. Repair or replace vacuum hose as necessary.
13. To check airtightness of fuel tank and fuel inlet pipe, disconnect EVAP line hose from charcoal canister by pinching both sides of connector together. Perform STEP 2 in illustration. (Scheme 95) Apply.58 psi (.040 kg/cm 2 ) air pressure to EVAP line hose so pressure inside fuel tank is.58 psi (.040 kg/cm 2 ). Check that pressure inside fuel tank holds steady for one minute.
14. If pressure inside fuel tank holds steady for one minute, reinstall EVAP line hose on charcoal canister. Go to next step. If pressure inside fuel will not hold steady for one minute, check for leaking hoses or pipes at fuel tank and fuel inlet pipe, or for leaks at fuel tank or installed components on fuel tank. If no leaks exist, replace fuel tank and fuel inlet pipe. Reinstall EVAP line hose on charcoal canister. Go to next step.
15. To check overfill check valve and cut-off valve, disconnect purge line hose and EVAP line hose from charcoal canister and install cap on air drain hose. Perform STEP 3 in illustration. (Scheme 95)
16. Apply.58 psi (.040 kg/cm 2 ) air pressure to purge line hose fitting on charcoal canister. Perform STEP 3 in illustration. (Scheme 95) Ensure air flows from EVAP line hose when air pressure is applied to purge line hose fitting on charcoal canister. If fuel tank is full of fuel, air may not flow from EVAP line hose, as overfill check valve may be closed. Ensure fuel tank is not full of fuel when checking for airflow at EVAP line hose.
17. If air flows from EVAP line hose, go to next step. If air does not flow from EVAP line hose, check for restrictions in EVAP line hose and vent line hose. If any hose is restricted, replace hose and recheck operation. If hoses are not restricted, replace overfill check valve and cut-off valve located on top of fuel tank. see scheme 163
18. Reinstall purge line hose and EVAP line hose on charcoal canister. To check air inlet line, disconnect air inlet line hose from charcoal canister. Perform STEP 4 in illustration. (Scheme 95) Apply air pressure to air inlet line hose. Air should flow through air inlet line hose. If air flows through air inlet line hose, go to next step. If air does not flow through air inlet line hose, check for restricted air inlet line hose or air inlet line.
19. To check charcoal canister, disconnect necessary electrical connectors and components for removal of charcoal canister. Disconnect purge line hose, EVAP line hose and air inlet line hose from charcoal canister if not previously done.
20. Push connector on vent line hose toward charcoal canister, pinch both sides of retainer on connector, and disconnect vent line hose with connector from charcoal canister. (Scheme 96)
21. Remove retaining nuts and charcoal canister. Inspect charcoal canister for cracks or damage. If charcoal canister is okay, go to next step. If charcoal canister is defective, replace charcoal canister.
22. Install cap on vent port on charcoal canister. (Scheme 97) Apply.26 psi (.018 kg/cm 2 ) air pressure to EVAP port while holding purge port closed. (Scheme 97) Ensure air flows freely from air drain port.
23. Apply.26 psi (.018 kg/cm 2 ) air pressure to EVAP port while holding air drain port and purge port closed. (Scheme 97) Ensure air does not flow from air inlet port.
24. Using vacuum pump, apply 1.01 in. Hg of vacuum to purge port. (Scheme 97) Ensure vacuum does not decrease when air inlet port is closed and that vacuum decreases when air inlet port is opened.
25. While holding air inlet port closed, use vacuum pump to apply 1.01 in. Hg of vacuum to EVAP port. (Scheme 97) Ensure air flows into purge port. Remove cap from vent port. Replace charcoal canister if defective.
26. Reinstall charcoal canister. If fuel EVAP system operates properly, it may be necessary to check operation of EVAP Vacuum Switching Valve (VSV), canister closed valve Vacuum Switching Valve (VSV) and vapor pressure sensor. See «EVAP VACUUM SWITCHING VALVE»(ref-133221-S30853527182002021900000), «CANISTER CLOSED VALVE VACUUM SWITCHING VALVE»(ref-133221-S07084902692002021900000) and «VAPOR PRESSURE SENSOR»(ref-133221-S28653838982002021900000).

Fuel EVAP System Test (Prius)

Note. Manufacturer provides testing information for testing airtightness of fuel tank and components along with testing of charcoal canister and fuel EVAP system.

Scheme 97

Scheme 98

Scheme 99

Scheme 100

1. Inspect all fuel EVAP system lines and connections for sharp bends or damage. It may be necessary to remove tailpipe and heat insulator for access to lines and connections. Fuel inlet pipe may also be referred to as fuel filler pipe. Inspect fuel inlet pipe for cracks, damage or fuel leakage. Inspect fuel tank cap for cracks or deformed gasket. Replace components if defective or damaged.
2. Start engine and warm engine to normal operating temperature. Shut engine off. Connect vacuum gauge from EVAP System Test Kit (00002-6872A) to EVAP service port. EVAP service port is located in engine compartment, in purge vacuum hose for EVAP system, near air cleaner assembly. EVAP service port contains a Green label for identification.
3. Operate EVAP Vacuum Switching Valve (VSV). If Toyota hand-held tester is available to operate EVAP VSV, go to next step. If Toyota hand-held tester is not available to operate EVAP VSV, go to step 5.
4. Connect hand-held tester to data link connector No. 3 at driver's side of instrument panel. see scheme 15 Start engine. Turn hand-held tester on. Select ACTIVE TEST MODE on hand-held tester. Using hand-held tester manufacturer's instructions, activate EVAP VSV. Go to step 6.
5. Disconnect electrical connector at EVAP VSV. EVAP VSV is located at passenger's side front corner of engine compartment, near air intake hose and contains Blue 2-pin electrical connector with Red/Blue and Black wires. see scheme 165 Using jumper wires, connect battery voltage and ground to electrical terminals on EVAP VSV to operate EVAP VSV. Start engine. Go to next step.
6. Check vacuum reading on vacuum gauge with engine idling. Vacuum reading should be.368-19.713 in. Hg (5.00-268.00 in. H2O) for over 5 seconds. If vacuum reading is within specification, go to next step. If vacuum reading is not within specification, check for loose or restricted vacuum hose to EVAP service port, or for malfunctioning EVAP VSV. To check EVAP VSV operation, see «EVAP VACUUM SWITCHING VALVE»(ref-133221-S30853527182002021900000).
7. Shut engine off. If using hand-held tester to operate EVAP VSV, stop operation of EVAP VSV. Leave hand-held tester connected to DLC No. 3. Go to next step. If connecting battery voltage to EVAP VSV to operate EVAP VSV, disconnect jumper wires and reconnect electrical connector on EVAP VSV. Go to next step.
8. Disconnect vacuum gauge from EVAP service port. Connect pressure gauge to EVAP service port. Install hose crimper on air drain hose near charcoal canister. (Scheme 98) Charcoal canister is located near fuel tank. see scheme 165
9. Apply 13.5-15.5 in. H2O of pressure to EVAP service port. After 2 minutes of applying pressure, pressure should be 7.7-8.8 in. H2O. If pressure is within specification, remove hose crimper and go to next step. If pressure cannot be maintained, remove hose crimper. Check for disconnected vacuum hose between EVAP VSV, charcoal canister and fuel tank. If vacuum hose is properly installed on EVAP VSV, charcoal canister and fuel tank, check for stuck open EVAP VSV. To check EVAP VSV operation, see «EVAP VACUUM SWITCHING VALVE»(ref-133221-S30853527182002021900000).
10. To check airtightness of fuel tank and fuel inlet pipe, operate Canister Closed Valve Vacuum Switching Valve (CCV VSV). If Toyota hand-held tester is available to operate CCV VSV, go to next step. If Toyota hand-held tester is not available to operate CCV VSV, go to step 12.
11. With hand-held tester still connected to data link connector No. 3, turn ignition on and then turn hand-held tester on. DO NOT start engine. Select ACTIVE TEST MODE on hand-held tester. Using hand-held tester manufacturer's instructions, activate CCV VSV. Go to step 13.
12. Remove glove box for access to Engine Control Module (ECM). For illustration of ECM location, see THEORY & OPERATION article. Turn ignition on. Connect jumper wire between body ground and terminal No. 13 (Blue wire) at ECM electrical connector E9. (Scheme 99) This is the CCV terminal at ECM which is the ground circuit for the CCV VSV. Go to next step.
13. Apply.232 psi (.016 kg/cm 2 ) of pressure to EVAP service port. Check that pressure can be held for 30 seconds. If pressure can be held for 30 seconds, turn ignition off. Remove pressure gauge and hand-held tester or jumper wire. Go to next step. If pressure cannot be held for 30 seconds, check for leaking hoses or pipes at fuel tank and fuel inlet pipe, or for leaks at fuel tank or installed components on fuel tank. If no leaks exist, replace fuel tank and fuel inlet pipe. Go to next step.
14. To check air inlet line, disconnect air inlet line hose from fresh air valve and air cleaner case. (Scheme 100) Fresh air valve is located on top of fuel tank. see scheme 165 Apply air pressure to air inlet line hose at air cleaner case. Ensure air flows from air inlet line hose at fresh air valve. If air flows from air inlet line hose, go to next step. If air does not flow from air inlet line hose, check for restrictions or damage to air inlet line and air inlet line hoses. If air inlet line or air inlet line hose is restricted, replace components as necessary.
15. Inspect air inlet line hoses and air inlet line for damage. If air inlet line and air inlet line hose are okay, reinstall air inlet line hoses. Go to next step. If air inlet line or air inlet line hose is defective, replace components as necessary.
16. To check charcoal canister, manufacturer states to remove fuel tank for access to charcoal canister. See «FUEL PUMP»(ref-133226-S07700574872002021900000) under FUEL SYSTEMS in REMOVAL, OVERHAUL & INSTALLATION - 4-CYLINDER article for removal of fuel tank. Disconnect necessary hoses for removal of charcoal canister if not previously done. Remove purge flow switching valve Vacuum Switching Valve (VSV) and retaining bolts for charcoal canister. Remove charcoal canister from fuel tank. Inspect charcoal canister for cracks or damage. If charcoal canister is okay, go to next step. If charcoal canister is defective, replace charcoal canister.
17. Note ports on charcoal canister. (Scheme 101) While holding port "C" closed, apply.71 psi (.05 kg/cm 2 ) air pressure to port "A". Ensure air flows freely from port "B".
18. Apply.71 psi (.05 kg/cm 2 ) air pressure to port "A". Ensure air flows freely from all other ports on charcoal canister. Replace charcoal canister if defective. Reinstall charcoal canister on fuel tank.
19. To check trap filter and fresh air valve, manufacturer states to remove fuel tank (if not already done) for access to trap filter and fresh air valve, as they are mounted on top of fuel tank. see scheme 165 Disconnect necessary hoses and electrical connectors for removal of Canister Closed Valve Vacuum Switching Valve (CCV VSV) and fresh air valve. Remove bolt and separate fresh air valve from CCV VSV. Remove bolts for CCV VSV and remove CCV VSV along with trap filter. Remove bolts and separate trap filter from CCV VSV.
20. Inspect trap filter and fresh air valve for cracks or damage. If trap filter and fresh air valve are okay, go to next step. If trap filter or fresh air valve is defective, replace components as necessary.
21. To check trap filter operation, apply light air pressure to port "A". Ensure air flows freely from port "B". (Scheme 101) Replace trap filter if defective. To check fresh air valve operation, apply light air pressure to port "A". Ensure air flows freely from ports "B" and "C". (Scheme 101) Replace fresh air valve if defective. Reinstall components on fuel tank.
22. If fuel EVAP system operates properly, it may be necessary to check operation of EVAP Vacuum Switching Valve (VSV), canister closed valve Vacuum Switching Valve (VSV), purge flow switching valve Vacuum Switching Valve (VSV) and vapor pressure sensor. See «EVAP VACUUM SWITCHING VALVE»(ref-133221-S30853527182002021900000), «CANISTER CLOSED VALVE VACUUM SWITCHING VALVE»(ref-133221-S06504774382002021900000), «PURGE FLOW SWITCHING VALVE VACUUM SWITCHING VALVE»(ref-133221-S40459302782002021900000) and «VAPOR PRESSURE SENSOR»(ref-133221-S13831683992002021900000).

Scheme 101

Scheme 102

Scheme 103

Scheme 104

Scheme 105

Scheme 106

Scheme 107

Scheme 108

Scheme 109

Scheme 110

Scheme 111

Scheme 112

Scheme 113

Scheme 114

Scheme 115

1. Disconnect electrical connector at Canister Closed Valve Vacuum Switching Valve (CCV VSV). (Scheme 102)- (Scheme 110). Remove CCV VSV. NOTE: On ECHO, charcoal canister must be removed for removal of CCV VSV. Charcoal canister is located near fuel tank. see scheme 163 For removal of CCV VSV, see «CANISTER CLOSED VALVE VACUUM SWITCHING VALVE»(ref-133226-S27644802982002021900000) under EMISSION SYSTEMS & SUB-SYSTEMS in REMOVAL, OVERHAUL & INSTALLATION - 4-CYLINDER article.
2. Using ohmmeter, check that continuity exists between electrical terminals on CCV VSV and that resistance is within specification. See «CANISTER CLOSED VALVE VACUUM SWITCHING VALVE RESISTANCE»(ref-133221-S02749464852002021900000) table. Replace CCV VSV if no continuity exists or resistance is not within specification. CANISTER CLOSED VALVE VACUUM SWITCHING VALVE RESISTANCE Application Ohms @ 68°F (20°C) Camry 24-30 Camry Solara & ECHO (1) Celica & Highlander 24-30 Corolla, MR2 & RAV4 25-30 Tacoma (1) (1) Resistance should be 25-30 ohms at 68°F (20°C) and 33-42 ohms at 248 °F (120°C).
3. Using ohmmeter, ensure no continuity exists between each electrical terminal and body of CCV VSV. Replace CCV VSV if continuity exists between electrical terminal and body of CCV VSV.
4. To test CCV VSV operation, apply air pressure to port "A". Ensure air flows from port "B". Perform STEP 1 in illustration. (Scheme 111)- see scheme 205.
5. Apply battery voltage and ground to electrical terminals on CCV VSV. Apply air pressure to port "A". Ensure air does not flow from port "B". Perform STEP 2 in illustration. (Scheme 111)- see scheme 205. Replace CCV VSV if defective.