Blinking red light on my 2010 mazda 3 key fob

car came with 2 key/fobs new
lost the second one>?
never have just one or go broke fast.

red lamp on dash is IMMO SECURITY LAMP
IT CUTS SPARK AND FUEL. (AND ENGINE FOR SURE)
there are only 3 CURES

1. THE DEALER FIXES IT
2. OR SOME LOCKSMITHS CAN., CALL THEM.
3. SOME CAR SHOPS CAN, CALL THEM.

BUY THIS CAR DEAD?OR JUST LOST THE FOB
IF JUST LOST THE ELECTRONICS IS GOOD
SO JUST SEE THE 3 CHOICES

Battery flat in key fob, transponder in key lost program or antenna in ignition barrel faulty.

Probably dirty inside, take it apart, clean all parts and put it together.

Most key fobs have a key way in the middle of the outside of them you have to take a screw driver and pry them open to get at battery at least that was how it was for my dodge .

Whether your key fob is damaged or just has a dying battery, there is a way for you to unlock your vehicle and start the car. Just follow the steps below:

1. Press and hold the auxiliary key release button on the underside of the key fob.
2. Grab the looped end at the top of your key fob.
3. Pull out the auxiliary key.
4. Use the auxiliary key to unlock the driver's side door.

[Read more: What to do when you're locked out of your car]

HOW TO START THE MAZDA 3 WITH A BROKEN OR DEAD KEY

Now that you've managed to enter the vehicle with the auxiliary key, you're going to need to know how to start your Mazda 3. At this point, the auxiliary key can be put back into the key fob, as the key fob can still be used to start your vehicle. This will only take a few extra steps.

1. Make sure the shifter is in the Park (P) or Neutral (N) position.
2. Depress the brake pedal.
3. The light on the engine start button should flash green.
4. Take your key fob and touch the back of it to the push button start.
5. When the green light on the engine start button stops flashing and remains continuously illuminated, press the push button start normally to start the engine.
6. It is recommended you allow the vehicle to idle for about 10 seconds.

I just figured out how to change the battery in the Advanced (keyless) fob for my 2010 Mazda CX9. You just need to take out the physical key, and use a small flat-head screwdriver to pop off the back cover. Then there is a black battery cover with an o-ring that just pulls up to reveal the CR-2032 Battery. Here are some pictures to explain better:

Make sure all of the doors, trunk & hood are securely closed.

2000 Mazda 626
Note: Make SURE the battery is new.
Instructions for programming ONE keyless remote fob.
1. Open the driver’s door & leave open.
2. Insert the key in the ignition.
3. Turn the key to the on and off position 3 times.
4. Remove the key from the ignition.
5. After door open chime stops, press the door open button 3 times.
6. After chime, press any fob key twice.
7. After second chime, press any fob key twice again.
8. After third chime, press any fob key twice again.
9. Press the door open button once.
10. The car should give another acknowledgement chime.
11. Test key fob.
This DOES work. I just programmed mine successfully today, three hours ago.