Mercury Montego key fob battery
Every model year listed for the Mercury Montego has a proven battery. The most common answer is CR2032. Rows below run oldest to newest; a year can appear twice when the car came with more than one kind of key.
- 2005-2007Remote (separate)
CR2032
FCC ID CWTWB1U331 / CWTWB1U345 / CWTWB1U311Two sites agree: americankeysupply.com and uhs-hardware.com (checked Nov 1, 2026)
Find CR2032 on Amazon
Changing the battery
Separate remote fob
- A separate fob has no key blade inside, so it opens with nothing but a coin or a small screwdriver.
- Turn it over: some older fobs use one small screw, newer ones just clip. Pry at the seam once any screw is out.
- Replace the cell, keeping the + side where it was, and check the small metal tab still touches it.
- Close the fob and test it. If it does not work, open it again and check the cell is seated flat.
A CR2032 is 20 mm across and 3.2 mm thick. CR2032, CR2025 and CR2016 share the same width but not the same thickness, so a swap between them can leave a loose contact or a case that will not close.
Keep spare coin cells away from small children. A swallowed coin cell can burn the throat within hours; if it happens, go to an emergency room at once.