The short answer: you can open the key fob to replace its battery by releasing the metal key, prying the shell apart along the seam, then replacing the battery and reassembling. After that, test the remote to confirm it works.
In this article, you’ll find a practical, step-by-step guide for safely accessing the internal battery of a 2019 Honda Passport key fob, including the tools you’ll need, how to avoid damaging the case or seals, and tips for a clean reassembly. The process is designed for standard customer battery replacement and may vary slightly by trim or fob revision, but the general method remains the same.
What you’ll need
Prepare these basic items before you start so you can complete the battery replacement without interruption.
- CR2032 3V lithium battery (confirm the exact battery type on the fob or in the owner’s manual)
- Small flat-head screwdriver or a coin that fits into the seam
- Clean, dry work surface; optional microfiber cloth to wipe fingerprints
- Optional: plastic pry tool to avoid scratching the case
Having the right tools helps you complete the replacement cleanly and reduces the risk of damaging the fob’s casing or internal contacts.
Step-by-step guide to opening and replacing the battery
Use this sequence to safely access the internal battery, then reassemble and test the fob.
- Remove the mechanical key: On the back of the fob, locate the small release latch and slide/pull the metal key blade out of the fob.
- Open the shell: With the fob facing you, insert a flat-head screwdriver or coin into the seam between the halves and gently twist to separate them. Do not force the clips; work slowly around the entire edge.
- Access the battery: Once open, locate the battery, noting its orientation (which side is up). Some designs have a small metal contact clip holding the battery in place.
- Replace with a new battery: Remove the old battery, insert the new CR2032 with the correct polarity (plus side facing up in most designs), and ensure it seats flat against the contacts.
- Reassemble the fob: Align the two halves and press them together until the clips snap into place. Reinsert the mechanical key blade if it was removed.
- Test the fob: Press the lock/unlock buttons and verify the LED indicator or car response confirms operation. If nothing happens, recheck battery orientation and reseal tightly.
Careful, deliberate handling helps preserve the fob’s water-resistance and electronics. If the fob does not reassemble cleanly or the LED does not blink after reassembly, consider professional help to avoid further damage.
Tips and cautions
Before reassembling fully, keep these cautions in mind to protect the fob and car electronics.
- Handle the battery with dry hands or wear gloves to avoid oils or moisture affecting contacts.
- Use a plastic or nylon tool rather than a metal tool to minimize the risk of shorting the contacts.
- Do not force the shell open or closed; if it feels stuck, check for additional release latches or clips.
- Inspect or replace any damaged O-ring or seal if the fob shows signs of wear; a compromised seal can permit moisture intrusion.
- Dispose of the old battery properly following local regulations.
Following these cautions helps preserve the fob’s lifespan and prevents water ingress or contact corrosion.
When to seek professional help
If you encounter difficulties, or if your fob shows signs of moisture ingress, damage, or the car does not respond after battery replacement, contact a dealer or automotive locksmith. They can replace the battery or service the remote without risking damage to the fob or vehicle security system.
Summary
Opening and replacing the battery on a 2019 Honda Passport key fob is a straightforward DIY task when you have the right tools and take care to avoid damaging the shell or electronics. Start by removing the key blade, then carefully pry the fob halves apart, replace the CR2032 battery with the correct polarity, reassemble, and test. If the fob remains unresponsive after replacement or shows signs of moisture, seek professional service. Regular inspection and careful handling help prolong the life of your key fob.