DISCHARGED LEAD-ACID BATTERY

id300300001200

Outline

Malfunction symptom	Discharged lead-acid battery
Description	—
Possible cause	Lead-acid battery performance decrease: •  Internal electrode plate deterioration Condition when lead-acid battery discharged power is greater than supplied power from DC-DC converter continues for a long period of time: •  Heavy use of electrical components while EV system is stopped and vehicle is not charging (DC-DC converter stopped) •  DC-DC converter malfunction ―  Fail-safe due to DC-DC converter related DTC detection ―  Terminal looseness •  Large power consumption ―  After-market electrical accessories with large power consumption are installed Electrical discharge is high when the vehicle is not used: •  Forget to turn off electrical components •  Heavy use of electrical components with main power switched to ACC •  Vehicle left for long period •  Large amount of back-up current (particularly be careful of after-market electrical accessories)
System wiring diagram	•  Not applicable
Connector diagram	•  Not applicable

Diagnostic Procedure

Step	Inspection	Results	Action
1	INSPECT LEAD-ACID BATTERY FOR MALFUNCTION •  Inspect the applicable part. (See LEAD-ACID BATTERY INSPECTION.) •  Is the part normal?	Yes	Go to the next step.
		No	Repair or replace the malfunctioning location and perform the repair completion verification. (See LEAD-ACID BATTERY RECHARGING.) (See LEAD-ACID BATTERY REMOVAL/INSTALLATION.)
2	VERIFY DC-DC CONVERTER DTCs •  Perform the DTC inspection for the DC-DC converter. (See DTC INSPECTION.) •  Is a DTC displayed?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting. (See DTC TABLE [DC-DC CONVERTER (e-SKYACTIV)].)
		No	Go to the next step.
3	INSPECT DC-DC CONVERTER LEAD-ACID SIDE BATTERY WIRING HARNESS INSTALLATION FOR LOOSENESS •  Inspect the installation condition of the DC-DC converter lead-acid side battery wiring harness. (See DC-DC CONVERTER REMOVAL/INSTALLATION.) •  Is there looseness in the installation of the battery wiring harness?	Yes	Repair the looseness in the installation of the battery wiring harness and perform the repair completion verification. (See DC-DC CONVERTER REMOVAL/INSTALLATION.)
		No	Go to the next step.
4	VERIFY HOW CUSTOMER USES VEHICLE •  Verify the following usage conditions based on the contents of the interview with the customer. ―  Heavy use of electrical components while EV system is stopped and vehicle is not charging (DC-DC converter stopped) ―  Forget to turn off electrical components ―  Heavy use of electrical components with main power switched to ACC ―  Vehicle left for long period ―  Large amount of back-up current (particularly be careful of after-market electrical accessories) •  Does the usage condition consume power from the lead-acid battery? Note •  Even if the lead-acid battery fully discharges once, if the DC-DC converter is normal, the lead-acid battery may become usable if the EV system is started with a booster cable and operated normally.	Yes	Measure the lead-acid battery discharge current under the usage conditions of the customer. Verify the specifications of the lead-acid battery, calculate the time it takes until discharge cutoff voltage is reached using a 5-h rate or 12-h rate, present the findings to the customer, and give advice on how to use the electrical components. Perform the repair completion verification.
		No	Go to the next step.
Repair completion verification	VERIFY THAT VEHICLE IS REPAIRED •  Install/connect the part removed/disconnected during the troubleshooting procedure. •  Has the malfunction symptom been eliminated?	Yes	Complete the symptom troubleshooting. (Explain contents of repair to customer)
		No	Refer to the CAN (controller area network) malfunction diagnosis flow to inspect for a CAN communication error.   (See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [L.H.D. (E)] .) (See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [R.H.D.] .)