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HV Battery Control System: Pre-Check

  1. Precaution 
    1. To distinguish a trouble and replace a defective part, take necessary preventive measures against an electric shock. See GENERAL INFORMATION .
    2. Some portions of the wiring harness in the THS vehicle have the circuits, to which a high voltage is applied. To prevent an electrical shock, be sure to observe the following:
      1. Wear insulated gloves during inspection.
      2. Remove a service plug and do not start any repair operation before 5 minutes have passed, then confirm that the voltage at the output terminals has dropped down to 12 V or less.
      3. Use insulated tools during inspection.
      4. When disengaging wiring connectors, hold the connector bodies to avoid pulling the wires. When engaging wiring connectors, be sure to engage them securely.
    3. Do not leave tools or parts (bolts, nuts, etc.) inside the cabin.
    4. Do not carry metallic objects such as mechanical pencils or scales.
    Fig 1: Identifying Warning Lights
    G02805571Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  2. Diagnosis System 
    1. Description
      • The HV Battery ECU has a self-diagnosis system by which malfunction in the computer itself or in Hybrid System is detected and the master warning light in the combination meter and the Hybrid system warning light in the multi-information display lights up.
        Fig 2: Connecting Toyota Hand-Held Tester To Data Link Connector 3 (DLC3) On Vehicle
        G02805572Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      • To check the Diagnostic Trouble Codes (DTC), connect the TOYOTA hand-held tester to the Data Link Connector 3 (DLC3) on the vehicle. The TOYOTA hand-held tester also enables you to erase the DTC and check freeze frame data and various forms of THS data.
      • Freeze frame data:

        Freeze frame data records the battery condition when a malfunction is detected.

        When troubleshooting, this is useful for knowing the battery condition.

        Fig 3: Identifying DLC3 Connector Terminals
        G02805573Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. NOTE: If your display shows UNABLE TO CONNECT TO VEHICLE when you have connected the cable of the TOYOTA hand-held tester to the DLC3, turned the motor switch ON and operated the tester, there is a problem in the vehicle or tool.
      • If communication is normal when the tool is connected to another vehicle, inspect the DLC3 on the original vehicle.
      • If communication is still not possible when the tool is connected to another vehicle, the problem is probably in the tool itself, so consult the Service Department.
      Fig 4: DLC3 Terminal Condition Chart
      G02805574Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Check the DLC3.

      The HV control ECU conforms to ISO 14230 for communication.

      The terminal arrangement of the DLC3 complies with SAEJ1962 and matches the ISO 14230 format.

  3. Inspect Diagnosis 
    1. Check the auxiliary battery.
      1. Measure the voltage of the auxiliary battery.

        Voltage: 10 - 15 V 

        Fig 5: Identifying Master Warning Light
        G02805575Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Inspect the auxiliary battery, fuses, fusible links, wiring harness, connectors and ground.
    2. Check the master warning light.
        NOTE: If the master warning light does not come on, suspect a burnt fuse, burnt bulb, or open in wiring harness.
        Fig 6: Identifying Ready Light
        G02805576Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      1. Turn the ignition switch ON and confirm that the master warning light comes on.
      2. When the READY light is ON, the master warning light should go off.

        If the lamp remains on, the diagnosis system has detected a malfunction or abnormality in the system.

        Fig 7: Connecting Toyota Hand-Held Tester To DLC3
        G02805577Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Check the DTC.
      1. Prepare a TOYOTA hand-held tester.
      2. Connect the TOYOTA hand-held tester to the DLC3.
      3. Turn the ignition switch ON and push the TOYOTA hand-held tester main switch ON.
      4. Use the TOYOTA hand-held tester to check the DTC and freeze frame data and note them down. (For operating instructions, see the TOYOTA handheld tester operator's manual).

        Since the HV battery ECU stores DTC and freeze frame data, when troubleshooting, check all of the DTC, write down the freeze fame data and perform inspection according to the procedures of Circuit Inspection.

        Because the HV battery ECU is communicating with the HV ECU, if any DTC is stored in the HV battery ECU, check and record DTC stored in the HV ECU. For tables for DTC, see PRE-CHECK .

      5. See a related article to confirm details of the DTC.
      Fig 8: Identifying Toyota Hand-Held Tester And DLC3
      G02805578Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      4. NOTE: Before clearing, check that DTC for the HV battery ECU, DTC for the ECU which is related with freeze frame data and the freeze frame data are recorded.
    4. Clear DTC after completion of repair.
      1. Connect the TOYOTA hand-held tester to the DLC3.
      2. Operate the TOYOTA hand-held tester to erase the DTC (See the TOYOTA hand-held tester operator's manual.).
  4. CHECK FOR INTERMITTENT PROBLEMS 
      NOTE: In the simulation test, reproduce the condition at trouble occurrence based on the customer's comments and the freeze frame data recorded with the DTC.
    1. Perform a simulation test ( HOW TO PROCEED WITH TROUBLESHOOTING ).
    2. CHECK THE CONNECTOR AND TERMINAL .
    3. .HANDLE THE CONNECTOR .
  5. Toyota Hand-Held Tester Display Items 
    TOYOTA HAND-HELD TESTER DISPLAY MEASUREMENT ITEMS

    TOYOTA hand-held tester display Measurement Item
    BATTERY SOC Battery State of charge
    ONB CHARGE TIME Cumulative number of times of on-board equalizing charging
    BATTERY LO TIME Cumulative number of times of battery dies
    DC INHIBIT TIME Cumulative number of times of discharge inhibition
    IB MAIN BATTERY IB main battery current (with correction)
    BATT BLOCK V# Battery block voltage
    BAT BLOCK MIN V Battery block minimum voltage
    MIN BAT BLOCK # Minimum voltage battery block
    BAT BLOCK MAX V Battery block maximum voltage
    MAX BAT BLOCK # Maximum voltage battery block
    BATT INSIDE AIR Ambient temperature inside battery pack
    BATTERY TOO HI # Cumulative number of times of too-high battery voltage
    VMF FAN VOLTAGE Battery cooling fan voltage
    AUX. BATT V Auxiliary battery voltage
    WIN Charge restriction value
    WOUT Discharge restriction value
    DELTA SOC Difference between MAX. and MIN. values of SOC at every battery block.
    SBLW FAN ST RQS SBL cooling fan stop request signal
    COOLING FAN HI Cooling fan operation in high speed
    COOLING FAN MID Cooling fan operation in middle speed
    COOLING FAN LO Cooling fan operation in low
    CCTL Off-board equalizing charge control signal
    EQCO DF RELAY EQCO dead front relay
    EQTR CHARGE ST EQTR uniform charging start signal
    ONBORD CHARGE On-board equalizing charging status
    PREONBORDECH Pre-On-board charging status
    NORMAL STATUS Normal status
    INSIDE RESIST # Inside resistance
    BATT TEMP# Battery temperature
    ECU CODE ECU code
    IG OFF HOUR Average time of IG OFF
    IGON HOUR Average time of IG ON
    ETOFFCHGHR Estimation of time to finish OFF BOARD
    DTC The number of stored DTC
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