Moderate⏱ 30 min - 1 h11 steps·Original on iFixit ↗

2025-2026 Kia Carnival MPV Hybrid 12V Battery Replacement

Follow this guide to remove and replace the 12V auxiliary battery in your Kia Carnival HEV (Hybrid Electric Vehicle).

The Carnival HEV uses the 12V auxiliary battery to power most things, including the power relays and computers. If the auxiliary battery drops too low, you won't be able to start your car, even if the high voltage traction battery is sufficiently charged. You'll need to charge the auxiliary battery at the jump point.

This guide is written with a 2025 SX Hybrid model.

Tools (5)

Phillips #1 Screwdriver buy ↗
10 mm deep socket buy ↗
12mm Socket (3/8in Drive) buy ↗
Socket Wrench buy ↗
Long Nose Pliers buy ↗

Step-by-step instructions

Battery information

The auxiliary battery is located underneath the center console inside the MPV. The factory battery is AGM60L-DIN:
Structure: AGM (absorbent glass mat), likely not deep cycle
Capacity: 60Ah at 20H
RC (reserve capacity): 100 min
CCA (cold cranking amps): 500A
Sizing: Standard DIN H5 with the following dimensions:
9.40-9.56 in wide, 6.77-6.92 in long, 6.47-6.63 in high, 7.36-7.51 in total height (with the vapor capture device on top of the battery
239-243 mm wide, 172-176 mm long, 164.5-168.5 mm high, 187-191 mm total height (with the vapor capture device on top of the battery)

Disconnect the battery

The auxiliary battery connector is located under the hood near the top-left corner of the fuse box. It's normally mounted to the chassis frame.
Firmly squeeze connector tab and pull it out of its socket.
***This disconnects the 12V battery positive terminal from the car, effectively cutting off 12V power. *** Door locks and power doors will stop working. You won't lose your saved settings/driver profiles though.

Passenger floor console cover information

The battery is accessible from the passenger floor console cover.
The cover is secured with multiple clips and a screw rivet.

Remove the floor console cover

Use a Phillips screwdriver to remove the screw from the cover fastener rivet.
If the screw spins freely, use a small flathead screwdriver to pry the screw out slightly so its threads engage.
Remove the screw and fastener rivet.

Pull the bottom edge of the console cover.
Firmly pull on the top edge of the console cover to release the clips.
Angle the console out of its recess and remove it.

Remove the battery clamp

Use a 12 mm socket and wrench to remove the three bolts securing the battery clamp.
Remove the battery clamp.

Disconnect the current sensor

Squeeze the battery current sensor connector's tab near the negative battery terminal and pull it out of its socket.

Disconnect the battery ground

Use a 12 mm socket and wrench to remove the bolt connecting the battery negative terminal to the chassis.
During reassembly, be sure to fasten this bolt tightly (26.5-32.4 Nm), or you'll encounter electrical problems.

Remove the battery

Don't try to fully remove the battery yet, as it's still connected by the positive terminal.
Slowly wiggle the battery out of its recess until you can access the terminals.
You'll encounter some resistance, as the battery still has a vent hose attached to it. You can try to disconnect it with long needle nose pliers, or let it disconnect by itself as you remove the battery.

Use a 10 mm long socket and wrench to loosen the nuts securing the battery terminals.
Disconnect the battery terminals and remove the battery.
During reassembly, tighten the nuts to 7.8-9.8 Nm.

Reassembly tip

The top of the battery has a vapor capture device, which shunts toxic gas through a vent tube. This can be challenging to reconnect during reassembly:
Slide the battery back into its recess.
Use a pair of long needle nose pliers or large tweezers to position the hose elbow at the capture device inlet.
Use your fingers or a screwdriver to press the elbow into the inlet.

Conclusion

To reassemble your device, follow these instructions in reverse order.

Guide content belongs to iFixit, license CC BY-NC-SA. Open original