The typical battery is a CR2032 3-volt coin cell.
In some cases, regional variations or older stock may use CR2025 or CR2016, so you should verify by opening the fob or checking the owner’s manual to be sure before purchasing a replacement.
How to verify and replace the battery
To avoid buying the wrong size, follow these steps to identify the exact battery size for your fob before replacement.
- Open the fob by prying along the seam with a small flat-head screwdriver, taking care not to damage the housing.
- Remove the existing coin cell and read the imprint on the battery (for example, CR2032, CR2025, or CR2016).
- If the imprint is unreadable, measure the coin’s diameter and thickness: CR2032 is 20 mm in diameter and 3.2 mm thick; CR2025 is 20 mm by 2.5 mm; CR2016 is 20 mm by 1.6 mm.
- When in doubt, replace with a fresh CR2032 3V battery, which is the most common size for Honda remotes from this era, and ensure you’re buying a reputable brand.
After replacement, reassemble the fob and test the buttons at a short range to confirm proper operation.
Notes on compatibility
While CR2032 is the common default for many 2004 Pilot fobs, some regional variants or aftermarket replacements may use other sizes. Always verify and, if possible, consult the owner's manual or dealer for the exact specification for your vehicle's market.
Summary
For a 2004 Honda Pilot key fob, the most common battery is a CR2032 3V coin cell. Confirm by examining the existing battery or the fob’s manual; if in doubt, use a fresh CR2032 from a reputable brand. Replacing the battery is a quick DIY task that typically restores remote functionality.