Inspection Procedure

1. If the hose is damaged, replace the vacuum hose assembly.
2. Check the air and vacuum hoses for looseness, disconnection and blockage.

NG: REPAIR OR REPLACE VACUUM HOSES 

Fig 1: Identifying Vacuum Tank

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

OK: Go to Next Step 

1. Start the engine.
2. Disconnect the vacuum hose from the air cleaner cap.
3. Check that the disconnected port located on the vacuum tank applies suction to your finger.

   OK: 

   Vacuum pressure exists. 

4. Reconnect the vacuum hose.

NG: CHECK AND REPLACE VACUUM SOURCE AND HOSES 

Fig 2: Identifying Air Cleaner Cap Vacuum Hose

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

OK: Go to Next Step 

1. Connect the oscilloscope between terminals ACM and E1 of the E5 and E7 ECM connectors.
2. Warm up the engine to normal operating temperature.
3. Turn the A/C switch on.
4. Measure the voltage between terminals ACM and E1 of the ECM connectors.

   Standard voltage 

   VOLTAGE SPECIFICATION
   
   

   Condition	Voltage
   Shift position is D, and engine speed is 850 RPM or less	Pulse generation
   Shift position is D, and engine speed is 950 RPM or more	9 to 14 V
   Shift position is P	9 to 14 V

OK: Go to step  6

Fig 3: Identifying ECM Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: Go to Next Step 

1. Disconnect the V2 VSV for ACM connector.
2. Measure the resistance between terminals 1 and 2.

   Standard resistance: 

   19 to 21 Ω at 20°C (68°F) 

3. Reconnect the VSV for ACM connector.

NG: REPLACE DUTY VACUUM SWITCHING VALVE 

Fig 4: Identifying Duty Vacuum Switching Valve Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

OK: Go to Next Step 

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 E5 ECM connector.
   3. Measure the resistance between the terminals of the wire harness side connectors and body ground.

      Standard resistance: 

      Check for open 

      TESTER CONNECTION SPECIFIED CONDITION
      
      

      Tester Connection	Specified Condition
      VSV for ACM (V2-2) - ACM (E5-3)	Below 1 Ω

      Check for open 

      TESTER CONNECTION SPECIFIED CONDITION
      
      

      Tester Connection	Specified Condition
      VSV for ACM (V2-2) or ACM (E5-3) - Body ground	10 kΩ or higher

   4. Reconnect the ECM connector.
2. Check the wire harness between the VSV for ACM and the EFI relay.
   1. Remove the EFI MAIN relay from the fusible link block.
   2. Measure the resistance between the wire harness side connectors.

      Standard resistance: 

      Check for open 

      TESTER CONNECTION SPECIFIED CONDITION
      
      

      Tester Connection	Specified Condition
      VSV for ACM (V2-1) - EFI MAIN relay terminal (3)	Below 1 Ω

   3. Reconnect the VSV for ACM connector.
   4. Reinstall the EFI MAIN relay.

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

Fig 5: Identifying VSV, ECM And EFI Relay Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

OK: REPLACE ECM  (See REMOVAL  )

1. Remove the VSV for ACM.
2. Check operation of the VSV for ACM when positive battery voltage is applied to the terminals of the VSV for ACM connector.

   Positive battery voltage is not applied: 

   The air from pipe G is flowing out through pipes E and H. 

   Positive battery voltage is applied: 

   The air from pipe F is flowing out through pipes E and H. 

3. Reinstall the VSV for ACM.

NG: REPLACE DUTY VACUUM SWITCHING VALVE 

Fig 6: Inspecting Duty Vacuum Switching Valve Operation

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

OK: Go to Next Step 

1. Disconnect the vacuum hose from the front engine mount insulator.
2. Using a vacuum pump, apply vacuum of 80 kPa (600 mmHg, 25 in.Hg) and wait for 1 minute.
3. Check that there is no change in the needle movement of the vacuum pump gauge.
4. Check that there is no fluid leakage caused by a break in the diaphragm.

   OK: 

   Vacuum pressure exists. 

5. Reconnect the vacuum hose.
   Fig 7: Inspecting Engine Mounting Insulator Assembly Front

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPLACE ENGINE MOUNTING INSULATOR ASSEMBLY FRONT 

OK: SYSTEM OK