Inspection Procedure

HINT:

Read freeze frame data using the intelligent tester. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air-fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction (See FREEZE FRAME DATA ).

1. CHECK FUSE (ETCS FUSE) 
   1. Remove the ETCS fuse from the engine room R/B.
   2. Measure the resistance of the ETCS fuse.

      Standard resistance: 

      Below 1 Ω 

   3. Reinstall the ETCS fuse.
      Fig 1: Identifying Engine Room Relay Block & ETCS

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   NG: REPLACE ETCS FUSE 

   OK: Go to Next Step 

2. INSPECT ECM (+BM VOLTAGE) 
   1. Disconnect the A10 ECM connector.
   2. Measure the voltage according to the value(s) in the table below.

      Standard voltage 

      VOLTAGE SPECIFICATION TABLE
      
      

      Tester Connection	Specified Condition
      +BM (A10-3) - Body ground	9 to 14 V

      Fig 2: Identifying A10 ECM Connector Terminals

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   3. Reconnect the ECM connector.

   OK: CHECK FOR INTERMITTENT PROBLEMS 

   NG: 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 R/B.
      2. Disconnect the A10 ECM connector.
      3. Measure the resistance according to the value(s) in the table below.

         Standard resistance (Check for open) 

         RESISTANCE REFERENCE (CHECK FOR OPEN)
         
         

         Tester Connection	Specified Condition
         Engine room R/B ETCS fuse terminal 2 - +BM (A10-3)	Below 1 Ω

         Standard resistance (Check for short) 

         RESISTANCE REFERENCE (CHECK FOR SHORT)
         
         

         Tester Connection	Specified Condition
         Engine room R/B ETCS fuse terminal 2 or +BM (A10-3) - 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 R/B.
      2. Disconnect the negative battery terminal.
      3. Disconnect the positive battery terminal.
      4. Measure the resistance according to the value(s) in the table below.

         Standard resistance (Check for open) 

         RESISTANCE REFERENCE (CHECK FOR OPEN)
         
         

         Tester Connection	Specified Condition
         Positive battery terminal - Engine room R/B ETCS fuse terminal 1	Below 1 Ω

         Standard resistance (Check for short) 

         RESISTANCE REFERENCE (CHECK FOR SHORT)
         
         

         Tester Connection	Specified Condition
         Positive battery terminal or Engine room R/B ETCS fuse terminal 1 - Body ground	10 kΩ or higher

         Fig 3: Identifying Engine Room Junction Block & A10 ECM Connector Terminals

         Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      5. Reinstall the ETCS fuse.
      6. Reconnect the positive battery terminal.
      7. Reconnect the negative battery terminal.

   NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

   OK: REPLACE ECM (See  REMOVAL  )