For the 2017 Honda Civic LX, the key fob battery is a CR2032 3V lithium coin cell. The car's main 12-volt starting battery is a separate component and not a "key battery."
Understanding the two batteries in the Civic
In everyday use, there are two distinct batteries: the large 12-volt battery that starts the engine and powers electrical systems, and the small coin-cell inside the key fob that runs remote functions. This article focuses on the key fob battery.
Key fob battery specifics for the 2017 Civic LX
The typical replacement for the Civic LX key fob is a CR2032 3-volt lithium coin cell. This size is standard for most Honda fobs from that era. If you have a fob variant or are unsure, check the back of the fob or consult the owner's manual, as there can be minor variations in some models.
How to verify the correct battery size
To confirm the exact size before you buy, inspect the battery inside the fob. Remove the cover carefully and read the size printed on the battery itself or compare its diameter and thickness to common coin cells.
Note: If you need to replace the car's main 12-volt battery, that is a different part installed in the engine bay, not the "key battery." This article is about the key fob battery.
Replacing the key fob battery
The following steps describe how to replace the key fob’s CR2032 battery safely and correctly.
- Gather the right battery: CR2032 3V lithium coin cell, a small flathead screwdriver or fob opening tool, and a clean workspace.
- Open the fob: Gently pry apart the two halves at the seam using a thin blade or your fingernail, taking care not to damage the electronics.
- Remove the old battery: Note the orientation (which side faces up) and lift it out.
- Insert the new battery: Place the CR2032 with the positive (+) side facing up, aligning it with the contacts.
- Reassemble and test: Snap the fob halves back together and test the remote to verify functionality.
If the remote still doesn’t work after replacement, recheck the orientation, ensure you didn’t damage the gasket or buttons, or consult a dealership if needed. A spare mechanical key can be used in some cases.
Where to buy the key fob battery
CR2032 batteries are widely available. Below are common places to purchase, often at low prices. Always confirm the size on the battery or in the fob's documentation before purchasing.
- Automotive parts stores (AutoZone, Advance Auto Parts, O'Reilly Auto Parts)
- Big-box retailers and pharmacies with electronics sections (Walmart, Target, CVS, Walgreens)
- Electronics retailers or online marketplaces (Amazon, battery specialty sites)
Concluding note: If you’re stocking up, consider buying a multi-pack of CR2032s for future fob replacements or other devices that use the same size.
Summary
The key fob battery for a 2017 Honda Civic LX is the CR2032 3-volt lithium coin cell. The car’s main starting battery is a separate 12-volt unit. By replacing the fob battery correctly, you maintain remote access without costly dealership service.