Another option:

Old style remote keys (with the rubber pad buttons) from the e38/e39/Z3/etc can be programmed to lock/unlock & arm/disarm the e38/e39/e46/e53 (perhaps the early X3, too) as long as they are on the same frequency as your new style diamond shaped key (315 MHz or 433 MHz).

The old style keys have removable backs and uses a replaceable CR2016 battery you can pick up just about anywhere...even the jewelry counter at Walmart.

Program it following the info posted above or below...as the 2nd, 3rd, or 4th remote key...starting with the button presses as outlined in STEP 3 after completing STEP 6 for the 1st key:

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• 2015 f06 650ix GC (Moonstone exterior/Cohiba brown Merino Leather interior)
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