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.
   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 

      Fig 1: Identifying Engine Room Relay Block

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: Go to next step 

3. CHECK HARNESS AND CONNECTOR (ECM - ETCS FUSE, ETCS FUSE - BATTERY) 
   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) 

         RESISTANCE REFERENCE
         
         

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

         Standard resistance (Check for short) 

         RESISTANCE REFERENCE
         
         

         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) 

         RESISTANCE REFERENCE
         
         

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

         Fig 2: Identifying Engine Room Relay Block And ETCS Fuse

         Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

         Standard resistance (Check for short) 

         RESISTANCE REFERENCE
         
         

         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.
   2. Measure the voltage between the terminals of the A21 and C20 ECM connectors.

      Standard voltage 

      VOLTAGE SPECIFICATION
      
      

      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) 

      Fig 3: Identifying A21 And C20 ECM Connector Terminal

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      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   )