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Dead Battery Check: Inspection

  1. CHECK BATTERY  .

    Perform Check battery (check items 1 - 3) to see if the battery is chargeable. Ref. to STARTING/CHARGING SYSTEMS(H4DOTC)>Battery>INSPECTION .

    Is there any fault with the battery?

    YES  :

    1. Charge or replace the battery. Ref. to STARTING/CHARGING SYSTEMS(H4DOTC)>Battery 
    2. GO to  2.

    No:  Currently, the battery is normal. (It is possible that the user charged or replaced the battery.) GO to  2.

  2. CHECK CHARGING SYSTEM. 

    Perform Check charging system (steps 1 - 4). Ref. to STARTING/CHARGING SYSTEMS(H4DOTC)>Charging System>INSPECTION 

    Is there any fault in the charging system?

    YES:  Repair or replace faulty parts.

    NO:  Go to Step 3.

  3. CHECK BATTERY RUN-OUT PREVENTION FUNCTION. 
    1. Turn the ignition switch to ON. (Engine OFF)
    2. Turn the room light ON, and keep the ON condition.
    3. Turn the ignition switch to OFF, wait for 20 minutes or more, and check if the room light automatically turns off
      NOTE: When the relay is stuck to the ON state, the battery run-out prevention function does not operate properly, which may cause battery run-out due to forced turn-off failure.

      Does the room light stay illuminated after 20 minutes?

      YES: 

      1. Repair or replace faulty parts. (The room light power supply circuit (including the relay) is faulty.) Ref. to SECURITY AND LOCKS>Relay and Fuse .
      2. Because battery run-out due to vehicle use conditions is possible, provide the user with the following advice. Battery run-out may occur more frequently after the following is experienced multiple times while the engine is stopped.
      3. Automatic turn-off of room light (Room light is left illuminated for 20 minutes or more)

        4. No:  GO to Step 4

  4. CHECK STANDBY CURRENT. 

    Measure the standby current while the room light is off in step 3-3. Ref. to STARTING/CHARGING SYSTEMS(H4DOTC)>Battery>INSPECTION > STANDBY CURRENT 

    NOTE: With the room light off, wait for five minutes and measure the standby current after it becomes stable.

    Is the standby current less than 70 mA?

    YES:  Check if there is any cause that increases the standby current temporarily. GO to  6.

    NO: 

    GO to  5.

  5. CHECK STANDBY CURRENT CHANGE (BEFORE/AFTER REMOVING/INSTALLING ELECTRICAL PART ACCESSORIES). 
    1. Check if electrical part accessories are installed. (Including after-market parts)
    2. Measure the standby current with the electrical part accessories installed.STARTING/CHARGING SYSTEMS(H4DOTC)>Battery>INSPECTION > STANDBY CURRENT 
    3. Measure the standby current with the electrical part accessories removed.STARTING/CHARGING SYSTEMS(H4DOTC)>Battery>INSPECTION > STANDBY CURRENT 
    NOTE: With the electrical part accessories removed, wait for five minutes and measure the standby current after it becomes stable.

    Does the standby current change from 70 mA or more less than 70 mA before/after removing/installing the electrical part accessories?

    YES:  Repair or replace defective electrical part accessories. (It is possible that the battery ran out due to increased standby current affected by the electrical part accessories.)

    NO: 

    1. Because there is a unit consuming large amounts of power, remove all fuses one by one to identify which system changes the standby current value significantly. (For the inspection order, refer to obtained results of all DTCs.)WIRING SYSTEM>Power Supply Circuit
    2. Check the related part, harness and connector of the system whose standby current has changed significantly.

  6. CHECK SWITCH INPUT FOR START CONDITIONS IS NOT OCCURRING. 
    Switch Operation
    Door lock switch Lock or unlock
    Door switch Door open/close
    Rear gate opener button Press the switch
    Room light switch Operate the switch
    Spot map light switch Press the switch
    Lighting switch Passing
    Hazard light switch Press the switch
    Stop light switch Depress the brake pedal
    Power seat switch Power seat operation
    Electronic parking brake switch Push or pull the switch

    Is DTC for ON/OFF stuck stored?

    Is switching of the ON/OFF contact point unstable?

    YES:  Repair or replace faulty parts. (It is possible that the battery ran out due to increased standby current periodically affected by the switch malfunction.)

    NO: 

    1. Currently, it is normal. Finish the diagnosis.
    2. Because battery run-out due to vehicle use conditions is possible, provide the user with the following advice. Battery run-out may occur more frequently after the following is experienced multiple times while the engine is stopped.
      • Automatic turn-off of room light (Room light is left illuminated for 20 minutes or more)
      • Automatic turn-off function of headlight (Headlight is left illuminated for 20 minutes or more)
      • Continuous wiper operation
      • Battery run-out prevention function (Left at ACC approximately 20 minutes or more, or left at ON approximately 60 minutes)
      • Recognize access key (The vehicle accidentally recognizes the access key through actions such as passing near the vehicle, opening/closing the entrance door, etc. Example: Illumination of welcome lighting)
      • Doors open (The function to monitor that all the doors are closed, such as during opening/closing of the front/rear doors while the rear gate is open, operates for a predetermined period of time.)
    3. Provide the user with the following advice for the battery charging.
      • The vehicle battery is charged while the vehicle is being driven.
      • When driving time that is ten minutes or less at a time happens repeatedly, or when the vehicle is not in use for ten days or more, perform battery charge driving in order to maintain the battery performance.
      • By performing battery charge driving (drive for 30 minutes or more as a guide), it may be possible to restore the charged state and maintain the battery performance.
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