Reading the Sonata battery label

The manual's Battery capacity label section explains each item on the label it illustrates:

From the Battery capacity label section of the 2027 Sonata owner's manual, read November 10, 2026. The label also lists a cold-test current (CCA). The manual says the actual battery label in the vehicle may differ from the illustration.

When you replace the battery, the manual says to always use a genuine Hyundai approved battery or the equivalent specified for your vehicle.

AGM battery rules and Idle Stop and Go

Because the Sonata's labeled battery is an Absorbent Glass Mat (AGM) battery, these rules from the manual apply:

From the Battery and Idle Stop and Go (ISG) sections of the 2027 Sonata owner's manual. The ISG section adds: use only a genuine Hyundai AGM battery for replacement, or the ISG system may not operate properly.

Sonata battery care from the owner's manual

For best battery service, the manual says:

• Keep the battery securely mounted.
• Keep the battery top clean and dry.
• Keep the terminals and connections clean, tight, and coated with petroleum jelly or terminal grease.
• Rinse any spilled acid off the battery right away with a solution of water and baking soda.
• If the car will not be used for an extended time, disconnect the battery cables.
• If you will not use the car for a long time in a cold area, disconnect the battery and keep it indoors, and always keep it fully charged to prevent case damage in low temperatures.
• Do not connect unauthorized electronic devices to the battery; they may discharge it.

Hyundai's normal maintenance schedule in the same manual lists battery condition as an inspection item every 8,000 miles or 12 months. Before winter, it says to inspect the battery and cables, since winter temperatures may affect battery performance; an authorized Hyundai dealer or a service station can check the charging level.

From the Battery, Normal maintenance schedule and winter driving sections of the 2027 Sonata owner's manual.

How to charge a Sonata battery

The manual gives two charging rates, depending on how the battery ran down:

From the Battery recharging section of the 2027 Sonata owner's manual. Use a fully automatic AGM charger for an AGM battery.

Before charging, turn off all accessories and press the Engine Start/Stop button to OFF. The manual says the battery must be removed from the vehicle and charged in a well-ventilated area, to wear eye protection, keep flames and sparks away, and stop or slow the charge if the cells begin boiling violently. Remove the negative cable first and install it last. When you are done, turn off the charger main switch, then unhook the negative clamp, then the positive clamp.

How to jump start a Sonata

Use only a 12 V power supply (a battery or jumper system), and do not try to push-start the car. The manual's jump-starting steps:

1. Position the vehicles close enough for the jumper cables to reach, without letting the vehicles touch. Keep away from fans and other moving parts in the engine compartment, even with the vehicles off.
2. Turn off all electrical devices such as the radio, lights and air conditioning. Put both vehicles in P (Park), apply the parking brakes and turn both vehicles off.
3. Open the hood and remove the engine compartment fuse box cover. Identify the positive (+) and negative (-) terminals correctly to avoid a reverse-polarity connection.
4. Connect one jumper cable to the red, positive (+) battery terminal of your Sonata, and the other end to the red, positive (+) battery or jumper terminal of the assisting vehicle.
5. Connect the second cable to the black, negative (-) battery or jumper terminal of the assisting vehicle, and the other end to the chassis ground of your Sonata. Do not connect it to the negative (-) jumper terminal of the discharged battery: a spark could cause the battery to explode.
6. Start the assisting vehicle, let it run at about 2,000 RPM for a few minutes, then start your Sonata.
7. Disconnect the cables in the exact reverse order: your chassis ground, the assisting vehicle's negative (-) terminal, the assisting vehicle's positive (+) terminal, then your Sonata's positive (+) jumper terminal.

Afterward, keep the Sonata running for at least 30 minutes at idle or driving; a completely discharged battery may need as long as 60 minutes of runtime to fully recharge. (The manual's Battery section gives a shorter figure for a jump from a good battery: drive it for 20-30 minutes before shutting it off.) If it does not start after a few attempts, have it inspected by an authorized Hyundai dealer.

From the Jump-starting and Battery recharging sections of the 2027 Sonata owner's manual.

What to reset after a battery change or disconnect

The manual lists these items as possibly needing a reset after the battery has been discharged or removed:

• Trip information (Current Trip, Since Refueling and the third trip mode)
• Integrated Memory System
• Power windows
• Sunroof
• Climate control system
• Clock
• Infotainment system

Planning a battery check? Schedule service or see our battery service near elkhart.

From the Reset items section of the 2027 Sonata owner's manual. Items apply where your car has them.

Hyundai of Goshen service hours

From Hyundai of Goshen's website, November 10, 2026. The website lists Monday to Saturday service hours and none for Sunday. Holiday hours can differ.