Inspection Procedure

HINT:

Read freeze frame data using a Techstream. Freeze frame data record the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data, from the time the malfunction occurred.

1. READ VALUE USING TECHSTREAM (+BM VOLTAGE) 
   1. Connect a Techstream to the DLC3.
   2. Turn the ignition switch to ON.
   3. Turn the tester ON.
   4. Select the following menu items: Powertrain / Engine and ECT / Data List / All Data / +BM Voltage.
   5. Read the value displayed on the tester.

      Standard voltage: 11 to 14 V 

   OK:  Go to step  5

   NG: Go to Next Step 

2. CHECK FUSE (ETCS FUSE) 
   1. Remove the ETCS fuse from the engine room relay block.
   Fig 1: Identifying ETCS Fuse
   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   2. Check the ETCS fuse resistance.

      Standard resistance: Below 1 Ω 

   3. Reinstall the ETCS fuse.

   NG: CHECK FOR SHORTS IN ALL HARNESSES AND CONNECTORS CONNECTED TO FUSE AND REPLACE FUSE 

   OK: Go to Next Step 

3. CHECK HARNESS AND CONNECTOR (ECM - ETCS FUSE, ETCS FUSE - BATTERY) 
   Fig 2: Identifying Harness And Connector (ECM - ETCS Fuse, ETCS Fuse - Battery)

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. Check the harness and connector between the ETCS fuse and ECM.
      1. Remove the ETCS fuse from the engine room relay block.
      2. Disconnect the A21 ECM connector.
      3. Check the resistance.

         Standard resistance (Check for open) 

         TESTER CONNECTIONS SPECIFIED CONDITIONS CHART
         
         

         Tester Connections	Specified Conditions
         ETCS fuse (2) - +BM (A21-3)	Below 1 Ω

         Standard resistance (Check for short) 

         TESTER CONNECTIONS SPECIFIED CONDITIONS CHART
         
         

         Tester Connections	Specified Conditions
         ETCS fuse (2) or +BM (A21-3) - Body ground	10 kΩ or higher

      4. Reinstall the ETCS fuse.
      5. Reconnect the ECM connector.
   2. Check the harness and connector between the ETCS fuse and positive battery cable.
      1. Remove the ETCS fuse from the engine room relay block.
      2. Disconnect the negative battery cable.
      3. Disconnect the positive battery cable.
      4. Check the resistance.

         Standard resistance (Check for open) 

         TESTER CONNECTIONS SPECIFIED CONDITIONS CHART
         
         

         Tester Connections	Specified Conditions
         Positive battery cable - ETCS fuse (1)	Below 1 Ω

         Standard resistance (Check for short) 

         TESTER CONNECTIONS SPECIFIED CONDITIONS CHART
         
         

         Tester Connections	Specified Conditions
         Positive battery cable or ETCS fuse (1) - Body ground	10 kΩ or higher

      5. Reinstall the ETCS fuse.
      6. Reconnect the positive battery cable.
      7. Reconnect the negative battery cable.

   NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

   OK: Go to Next Step 

4. INSPECT ECM (+BM TERMINAL VOLTAGE) 
   1. Disconnect the A21 and C20 ECM connectors.
   Fig 3: Identifying A21 And C20 ECM Connectors
   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   2. Measure the voltage between the terminals of the A21 and C20 ECM connectors.

      Standard voltage 

      TESTER CONNECTIONS SPECIFIED CONDITIONS CHART
      
      

      Tester Connections	Specified Conditions
      +BM (A21-3) - E1 (C20-104)	11 to 14 V
      +BM (A21-3) - ME01 (C20-43)	11 to 14 V

   3. Reconnect the ECM connectors.

   NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (TERMINAL E1 AND ME01 BODY GROUND) 

   OK: REPLACE ECM (See  REMOVAL   ) 

5. INSPECT BATTERY 
   1. Check that the battery is not depleted.

      OK: Battery is not depleted 

   NG: REPLACE BATTERY 

   OK: Go to Next Step 

6. CHECK BATTERY TERMINAL 
   1. Check that the battery terminals and ECM ground are not loose or corroded.

      OK: Battery terminals and ECM ground are not loose or corroded 

   NG: REPAIR OR REPLACE BATTERY TERMINAL 

   OK: CHECK FOR INTERMITTENT PROBLEMS (See  CHECK FOR INTERMITTENT PROBLEMS   )