Inspection Procedure

HINT:

Read freeze frame data using the intelligent tester. The ECM (Included in HV control ECU) records vehicle and driving condition information as freeze frame data the moment a DTC is stored. 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. CHECK FUSE (ETCS FUSE) 
   1. Remove the ETCS fuse from the engine R/B No. 4.
   2. Check the ETCS fuse resistance.

      Standard resistance: 

      Below 1 Ω 

   3. Reinstall the ETCS fuse.

   NG: CHECK FOR SHORT IN ALL HARNESS AND COMPONENTS CONNECTED TO FUSE 

   Fig 1: Identifying ETCS Fuse

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   OK: Go to next step 

2. INSPECT HV CONTROL ECU (+BM VOLTAGE) 
   1. Measure the voltage between the terminals of the H31 and H34 HV control ECU connectors.

      Standard voltage 

      TESTER CONNECTION AND SPECIFIED CONDITION
      
      

      Tester Connection	Specified Condition
      +BM (H34-3) - ME01 (H31-4)	9 to 14 V

   OK: CHECK FOR INTERMITTENT PROBLEMS 

   Fig 2: Identifying H31 And H34 HV Control ECU Connectors Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   NG: Go to next step 

3. CHECK HARNESS AND CONNECTOR (HV CONTROL ECU - ETCS FUSE, ETCS FUSE BATTERY) 
   1. Check the harness and connector between the ETCS fuse and HV control ECU.
      1. Remove the ETCS fuse from the engine R/B No. 4.
      2. Disconnect the H34 HV control ECU connector.
      3. Measure the resistance according to the value(s) in the table below.

         Standard resistance (Check for open) 

         TESTER CONNECTION AND SPECIFIED CONDITION
         
         

         Tester Connection	Specified Condition
         ETCS fuse (2) - +BM (H34-3)	Below 1 Ω

         Standard resistance (Check for short) 

         TESTER CONNECTION AND SPECIFIED CONDITION
         
         

         Tester Connection	Specified Condition
         ETCS fuse (2) or +BM (H34-3) - Body ground	10 kΩ or higher

      4. Reinstall the ETCS fuse.
      5. Reconnect the HV control ECU connector.
   2. Check the harness and connector between the ETCS fuse and positive battery cable.
      1. Remove the ETCS fuse from the engine R/B No. 4.
      2. Disconnect the positive battery cable.
      3. Measure the resistance according to the value(s) in the table below.

         Standard resistance (Check for open) 

         TESTER CONNECTION AND SPECIFIED CONDITION
         
         

         Tester Connection	Specified Condition
         Positive battery cable - ETCS fuse (1)	Below 1 Ω

         Standard resistance (Check for short) 

         TESTER CONNECTION AND SPECIFIED CONDITION
         
         

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

      4. Reinstall the ETCS fuse.
      5. Reconnect the positive battery cable.

   NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

   Fig 3: Identifying ETCS Fuse

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   OK: REPLACE HV CONTROL ECU