Inspection Procedure

CHECK VACUUM HOSES
1. Check whether the cap of vacuum hose is missing or not.
2. If the hose is damaged, replace the vacuum hose assembly.
3. Check the air and vacuum hoses for looseness, disconnection and blockage.
Fig 1: Identifying Vacuum Control Circuit
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1. OK: GO TO NEXT STEP.
2. NG: REPAIR OR REPLACE VACUUM HOSES
CHECK VACUUM
1. Start the engine.
2. Disconnect the vacuum hose from the vacuum tank.
  
  Fig 2: Disconnecting Vacuum Hose From Vacuum Tank
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3. Check that an unconnected port located on the vacuum tank applies suction to your finger.
4. Reconnect the vacuum hose.
1. OK: GO TO NEXT STEP.
2. NG: CHECK AND REPLACE VACUUM SOURCE AND HOSES
INSPECT ECM
1. Connect the oscilloscope between terminals ACM and of the E7 ECM connector.
2. Warm up engine to normal operating temperature.
3. Turn the A/C switch on.
4. Measure the voltage between terminals ACM and E1 of the E7 ECM connector.
Fig 3: Identifying ECM E7 Connector Terminals
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Fig 4: Identifying Oscilloscope Pattern
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Result:

Fig 5: Result Description Chart
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1. OK: Go to step 6
2. NG: GO TO NEXT STEP.
INSPECT DUTY VACUUM SWITCHING VALVE (RESISTANCE)
1. Disconnect the V2 VSV for ACM connector.
2. Measure the resistance between the terminals 1 and 2.
  
  Fig 6: Identifying VSV For ACM Connector Terminals
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  1. Resistance: 19 to 21 Ω at 20°C (68°F)
3. Reconnect the VSV for ACM connector.
1. OK: GO TO NEXT STEP.
2. NG: REPLACE DUTY VACUUM SWITCHING VALVE
CHECK HARNESS AND CONNECTOR (VSV FOR ACM - ECM, VSV FOR ACM - EFI RELAY)
1. Check the wire harness between the VSV for ACM connector and the ECM connector.
  1. Disconnect the V2 VSV for ACM connector.
  2. Disconnect the E7 ECM connector.
  3. Check the resistance between the wire harness side connectors.
    
    Fig 7: Identifying VSV For ACM Connector Terminals
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    Fig 8: Identifying ECM E7 Connector Terminal
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    Standard (Check for open):
    
    Fig 9: Specified Conditions
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    Standard (Check for short):
    
    Fig 10: Specified Conditions
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  4. Reconnect the VSV for ACM connector.
  5. Reconnect the ECM connector.
2. Check the wire harness between the VSV for ACM and the EFI relay.
  1. Inspect the EFI No. 2 fuse.
    - Remove the EFI No. 2 fuse from the fusible link block.
    - Check for continuity in the EFI No. 2 fuse.
      1. Standard: Continuity
    - Reinstall the EFI No. 2 fuse.
  2. Disconnect the V2 VSV for ACM connector
  3. Remove the EFI relay from the engine room R/B.
    
    Fig 11: Identifying EFI Relay Location & Terminals
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  4. Check the resistance between the wire harness side connectors.
    Standard (Check for open):
    
    Fig 12: Specified Conditions
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  5. Reconnect the VSV for ACM connector.
  6. Reinstall the EFI relay.
1. OK: REPLACE ECM (See REPLACEMENT in ENGINE CONTROL SYSTEM )
2. NG: REPAIR OR REPLACE HARNESS OR CONNECTOR.
INSPECT DUTY VACUUM SWITCHING VALVE (OPERATION)
1. Remove the VSV for ACM.
2. Check operation of the VSV for ACM when battery positive voltage is applied to the terminals of the VSV for ACM connector.
  
  Fig 13: Checking Operation Of VSV For ACM
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  1. Battery positive voltage is not applied:
  2. The air from pipe G is flowing out through pipes E and H.
  3. Battery positive voltage is applied:
  4. The air from pipe F is flowing out through pipes E and H.
3. Reinstall the VSV for ACM.
1. OK: GO TO NEXT STEP.
2. NG: REPLACE DUTY VACUUM SWITCHING VALVE
INSPECT ENGINE MOUNTING INSULATOR ASSY FRONT
1. Disconnect the vacuum hose from the front engine mount insulator.
2. Using MITYVAC (Hand-held Vacuum Pump), apply vacuum of 80 kPa (600 mm Hg, 25 in.Hg) and wait for 1 minute.
  
  Fig 14: Testing Lower Diaphragm For Leaks
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
3. Check that there is no change in the needle movement of the MITYVAC.
4. Check that there is no fluid leakage caused by a brake of a lower diaphragm.
5. Reconnect the vacuum hose.
1. OK: SYSTEM OK
2. NG: REPLACE ENGINE MOUNTING INSULATOR ASSY FRONT