Dead Battery Check: Inspection

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

Is there any abnormality in the battery?

Yes:
1. Charge or replace the battery. Ref. to STARTING/CHARGING SYSTEMS (H4DOTC)>BATTERY .
2. Go to 2.
No: The current battery state is normal. (It is possible that the user charged or replaced the battery.) Go to 2.
CHECK CHARGING SYSTEM .
Check the charging system (steps 1 - 4). Ref. to STARTING/CHARGING SYSTEMS (H4DOTC)>CHARGING SYSTEM>INSPECTION .

Is there any abnormality in the charging system?

Yes: Repair or replace faulty parts.

No: Go to 3.
CHECK BATTERY RUN-OUT PREVENTION FUNCTION .
1. Turn the ignition switch to ON. (Engine OFF)
2. Turn the room light on and keep it lit.
3. Turn the ignition switch to OFF, wait for 20 minutes or more, and check if the room light automatically goes 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 still Illuminate even after 20 minutes?

Yes:
1. Repair or replace faulty parts. (Room light power supply circuit (including relays) is faulty.) Ref. to BODY CONTROL/COMMUNICATION SYSTEM>RELAY AND FUSE .
2. Because battery discharge may be due to vehicle use conditions, provide the user with the following advice.
If you experience the following situation several times with the engine stopped, the battery is likely to be discharged.
- Automatic turn-off of room light (Room light is left illuminated for 20 minutes or more)
No: Go to 4.
CHECK STANDBY CURRENT .
In step 3-3, measure the standby current with the room light off. 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.
CHECK CHANGES IN STANDBY CURRENT (BEFORE/AFTER REMOVAL OF ELECTRICAL ACCESSORIES) .
1. Check that electrical accessories are installed. (Including after-market parts)
2. Measure the standby current with electrical accessories installed. Ref. to STARTING/CHARGING SYSTEMS (H4DOTC)>BATTERY>INSPECTION>STANDBY CURRENT .
3. Measure the standby current with electrical accessories removed. Ref. to STARTING/CHARGING SYSTEMS (H4DOTC)>BATTERY>INSPECTION>STANDBY CURRENT .
NOTE: Wait for five minutes with electrical accessories removed until the standby current stabilizes, and then measure the standby current.

Does the standby current change from 70 mA or more less than 70 mA before/after removal of electrical accessories?

Yes: Repair or replace the corresponding electrical accessories. (It is possible that the standby current increased due to electrical accessories, discharging the battery.)

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 the results of all DTCs obtained.) Ref. to WIRING SYSTEM>POWER SUPPLY CIRCUIT .
2. Check the related part, harness and connector of the system whose standby current has changed significantly.

CHECK THAT SWITCH INPUT (STARTUP CONDITION) DOES NOT OCCUR .

Typical examples of switches that operate according to the ignition switch OFF operation

Switch	Operation
Door lock switch	Lock or unlock
Door switch	Door open/close
Rear gate opener button	Pressing the switch
Room light switch	Switching the switch
Spot map light switch	Pressing the switch
Lighting switch	Passing
Hazard light switch	Pressing the switch
Stop light switch	Depress the brake pedal
Power seat switch	Power seat operation
Electronic parking brake switch	Pressing or pulling the switch

Are DTCs related to ON/OFF stuck stored?

Is switching of ON/OFF contact unstable?

Yes: Repair or replace faulty parts. (It is possible that the standby current increased periodically and repeatedly due to a switch malfunction, discharging the battery.)

No:

Currently, it is normal. Finish the diagnosis.
Because battery discharge may be due to vehicle use conditions, provide the user with the following advice.
If you experience the following situation several times with the engine stopped, the battery is likely to be discharged.
- 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)
- Wiper continuous operation
- Battery discharge prevention (The ignition switch is left unattached for approx. 20 minutes as ACC or for approx. 60 minutes as ON.)
- Access key recognition (The vehicle recognizes the access key, for example, when the key is carried near the vehicle or when an entrance door is opened/closed. e.g., welcome lighting illumination)
- 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.)
Provide the user with the following advice on battery charging.
- The vehicle battery is charged while the vehicle is being driven.
- It is necessary to drive the vehicle to charge the battery and maintain its performance if each driving duration is often less than 10 minutes or if the vehicle is not used for 10 days or more.
- It is possible that the battery charge condition is recovered and its performance is maintained by driving the vehicle (driving for 30 minutes or more is recommended).