No. 3 transmitter id code cannot be reprogrammed
Location indexMazda 6 Service Manual: Roof molding installation
1. Attach the roof molding to the T stud at the A section.
2. Press in the roof molding along the direction (1) shown in the figure and
attach it to the clip A at the B section.
3. Hook the roof molding to the clip B at the C section, press it in, and
attach the roof molding to the clip B.
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Mazda 6 Service Manual: Illuminated Entry System
When the illuminated entry system operates, the overhead lights, the courtesy
lights, and an ambient light* turn on in the following conditions:
The driver's door is unlocked after the ignition is switched OFF.
The ignition is switched OFF with all doors closed.
NOTE
(Overhead lights) ...