MK3 Keys! ?


Rather a long story and tale of woe, So when you’re sitting comfortably I’ll begin.

I’ve recently purchased my first MX5. It’s a MK3 2.0l Sport Coupe. I Love it.  It was a private sale and unfortunately only came with one key. I was aghast by the price of  a replacement key from a Mazda dealer so after a couple of days recovering from the shock I set about finding an alternative route. A website called supplied me with a basic key from a photograph of the original and also told me what the key code was; very impressive. With loins girded I took this new key back to the Mazda dealer to have its chip enabled. They did this in the time it took me to drink only one cup of their complementary coffee for a charge £15.00. (I’ll drink quicker next time, perhaps take my partner too). 

 Things were looking good until I realised that if the car had been locked using the original key the new basic key would not disarm the alarm (no remote functions). beep, beep, beep!

 Not one to beaten easily I turned to e-bay and duly bought a four button remote with a blank blade. I had the blade cut at my local key cutters and dashed back to the car full of the joys of spring. It fitted all the locks yipee! 

Over the weeks I had become increasingly well read on the subject of Mazda keys and foolishly thought I could code the little blighter myself. Happily pushing the two good coded keys in and out of the ignition before inserting the 3rd key had no effect. So for plan  ‘B’ This one involves switching the ignition on and off a number of times followed by opening and closing the drivers door like some deranged mono-winged bat. This had some effect (other than amusing the neighbours) and the car obliged by going into program mode. The new remote worked however the ignition remained disabled. Worse still I discovered that the original key remote had now been overridden. For the moment I have returned things to their original state and am resting whilst I re-group. Can anybody offer any help on this matter or must I gather a large group of coffee drinkers in an attempt to mitigate the cost of another visit to the Mazda dealer?

  Thanks in advance for your help.    Louise.

Hi Louise, having got my self comfy, armed with a mug of tea and a pack of devilishy tasty Minstrels I read your plight, after 20mins having eaten all my minstrels, dunked 1/2 pack of malted milk biscuits in me tea (common as muck) I read again with glasses on this time and everything came all so clear Big Smile…joking aside I can help somewhat in supplying you the dealer info sheet on re-programming your remotes, Pm me your email address and I will send forthwith. 

No doubt a fellow member here Speedy will put his two-penneth worth in as he too had misfortune of mis-coded remotes.

Regards,  Paul

Hi Louise

I too had a problem with two keys and one only working, did the door closed/ shut ignition off/on routine sounds very similar to the one you have tried, sadly to no avail as I also had no keys working then the other non working key worked so left it there, I have received the dealer info sheet from Paul but have not tried it, so cannot confirm it works, only too say it has more closing shutting on offs than the original one I tried. Hopefully when Paul (TC) send’s you the info it will work for you, let us know.

K Regards


 Modern alarms change the code on a random but known patern.


If you only use one key all the time the “spare” key will lose its patern and not work.

A lot of these on off door opening sequences are to re align the 2nd key to the sequence…not to reprogram it.


This might be the issue you have.

I swop my keys over every so often (on the Skoda) to stop this occuring.


As for the Mk3…mine dosn,t have any keysSad


If all else fails contact mazdamender for advice im sure he would know




I also bought a car (2006 2.0 sport) with only one key and am looking for an extra key. From what I can tell the answer seems to be, buy one on ebay, have the blank blade cut to match and then reprogramme it to the alarm using the opening/closing/ignition technique mentioned above. Is this about right and can any correct era mazda 4 button fob be recoded?

Thanks in adavance,



Hi <o:p></o:p>

 The answer to coding Mk3 keys is in two parts. (1) Coding the transponder.  (2) Coding the remote key fob.<o:p></o:p>

 I have set out the procedures below and also included a snag list with possible answers.<o:p></o:p>

<o:p> </o:p>

It would seem that all 4 button remotes are the same. However, if you remove the blade from the end of your good key you will find some tiny print inside the key fob.  I could only read this through a hand lens. There is a date and a several codes. I think a relevant date and the SK126-01 are the pertinent bits.<o:p></o:p>

<o:p> </o:p>

Part 1. Coding the transponder<o:p></o:p>

<o:p> </o:p>

Items needed:<o:p></o:p>

  1. 2x pre-programmed transponder keys!
  2. 1x new transponder key.

The timing is critical to this procedure so best to read the whole thing before starting.<o:p></o:p>

<o:p> </o:p>

  1. Insert one of the pre-programmed transponder keys and turn the ignition to ‘on’ leave on for at least one second (I waited until the red key symbol in the instrument cluster extinguished), remove the key from the ignition.
  2. Within 5 seconds insert the second pre-programmed key and turn the ignition ‘on’ for at least one second but not longer than 5 seconds (use the key symbol for this as well) then remove the second key.
  3. Within 10 seconds insert the new key in the ignition and turn to ‘on’, If you are successful the red key light will illuminate and then extinguish after about a second.

<o:p> </o:p>

  If unsuccessful the red key light will flash. Wait one minute and then start again.<o:p></o:p>

<o:p> </o:p>

<o:p> </o:p>

<o:p> </o:p>

Part 2. Synchronising the Remote Control Key Fobs<o:p></o:p>

<o:p> </o:p>

       1. Open the driver’s door.<o:p></o:p>

<o:p> </o:p>

  1. Place the good key in the ignition and switch on an off three times.
  1. Press the door courtesy light switch 3 times (equates to opening and closing the door three times). The central locking will clunk twice. If not wait one minute and then start again.
  1. Within 5 seconds press the unlock button on the first (good) remote.  Central locking should clunk again. Leave this key in the ignition.
  1. Within 5 seconds press the unlock button on the second remote. It doesn’t need to be in the ignition, just within range of the first remote. (More clunking.)

6. It is recommended to wait a few seconds then press the unlock button on the second key again. This apparently fills the third space in the car’s key code memory bank. <o:p></o:p>

<o:p> </o:p>

<o:p> </o:p>

<o:p> </o:p><o:p> </o:p>

<o:p> </o:p>

Pitfalls to look out for and possible solutions:<o:p></o:p>

<o:p> </o:p>

  1. The need for two good coded keys to start coding the transponder.

 If you only have one get a copy made, I can recommend Just send them a photo and they will supply a basic key, cut and with an integral transponder (un-coded)  ~£20.00.<o:p></o:p>

Take keys and car to Mazda dealer. They seem able to code the new key on its own (a secret I’m not yet privy to) ~£17.00. Drink their coffee, eat the biscuits!<o:p></o:p>

<o:p> </o:p>

  1. Not all the blank blades sold on e-bay have a transponder in them! (very dirty trick)
 I found this out by disassembling one. Cheap but not at all cheerful!  (Avoid the cheapest) 

<o:p> </o:p>

  1. Some e-bay key dealers seem to ‘shill bid’ to push the price up, then issue a second   chance offer at the value of your last bid. I payed £52.00 in the end for a remote key fob and blank blade (with transducer) but I guess you could do better on a good day.

The whole thing cost us £102.00 in the end and for that we have two extra keys. Not a cheap undertaking but comparatively cheap when compared to the £175.00 for one key quoted by Mazda. Incidentally Holdcroft’s in Hanley quoted £230.00 for the same job!! <o:p></o:p>

<o:p> </o:p>

This took us over a month to work out but was, in the end, satisfyingly successful. <o:p></o:p>

 Hope this helps and good luck. 

Please let us know if you were succesful.<o:p></o:p>

<o:p> </o:p>

<o:p> </o:p>Louise & John          <o:p></o:p>


Firstly thanks for the thorough response!

So far I have carried out the first part (yes it’s taken me a while) and can also recommend, not sure how they do it from a photograph, but it certainly fits the locks.I’ve just called a dealer to recode the transponder in the second key and they quoted between £50 -£75 plus VAT at different dealers, which seems rather a lot. Is a main dealer the only option or does anyone else have any suggestions? I’ve had a look around the net but without much luck!





Sorry for diging up an old post but…  I have a 2006 MK3

I have two keys…  The original Mazda key with fob and a second key which just starts the engine and has no fob.  

So I just need a fob for the second key to allow me to turn the alarm on and off.  

Can I pick up something like these below and just do the second step to program the fob allowing me to turn alarm on and off etc ?


Yep, or even better if that second link you posted is a genuine new blank key,
you could in theory get that cut and programme the new key and remote using
both stages above. You need 2 working keys to programme a third, or one working remote to programme a second. I’ve done them fine off eBay but bear in mind some secondhand stuff may not be good.

Separate your good key from the fob first (owners manual) and check whether it’s Mitsubishi or Visteon, you need the right one. Mine’s 4 button Mitsubishi below. I took the remote to the car without the key and found it works fine. I also took the key to the unlocked car without having the remote in range and it starts and works fine, so the 2 do seem to have independent functions.



The one I have doesn’t have any markins inside but I know its a Mitsubishi from the circuit board near the battery.  It has the Mitsubishi logo and a relevant part number on the circuit board.  So this maywell be a replacement shell I am thining.  Whatever…  as long as it works :stuck_out_tongue:

I will pick up one of these ebay ones and give it ago.  Like I said all I really need I think is a way of remote unlocking and switching off the alarm as a backup / for my wife.

Oh yeah…  Never thought about taking the fob part to the car without the key…  Doh :stuck_out_tongue:

Well I won the eBay auction for the full fob with uncut blade for £25 :slight_smile:

Been away on holiday and came home today to find it waiting for me :) 

Managed to reprogram the alarm part on the second attempt. :slight_smile: over the moon :). So now have two work keys :) 

will look into getting the blade cut and transponder working on this new set so I can have two genuine Mazda keys for it and then still have an additional spare.

So chuffed I pulled this off for such little money. Thanks for the help:)

Went to Timpsons today and they cut the blade for £3 but said it was at my own risk because they can’t replace it blah blah blah.  Said no problem just give it ago.  Anyway the key works fine in the locks and in the ignition slot.

Tried too reprogram it using the technique above but it won’t work.  I have noticed the key has a mafacturing defect as the key is the wrong way around.  So I wonder if there is a working transpnder inside or not.  But tried it about ten times and pretty sure my timing is as stated above but nothing.

So a bit gutted about that but I now at least have an alarm transmitter fob for the spare key so a good outcome never the less.

Just. Acquired an 07 mk3. The keys would not work central locking. New battery followed the instructions to reset all ok. Many thanks to this posting

i just bought a key from timpsons.
he programmed the new key chip to match (no buttons) & it works great without setting off alarms & immobiliser.

Sorry to bump an old thread.  I recently bought a NC, it came with two keys, one four button fob/blade key, and just a regular key programmed to the car.  I never read this thread properly and bought a Visteon four button fob off ebay, this didn’t work as mine was a Mitsubishi one.  I have since bought a used Mitsubishi one and programmed the remote, no problems as listed above, I sold the Visteon one on.

Now I just need to sort out the blade key.  The Mitsubishi one I bought came complete key etc.  Can I just replace the actual blade, or do I have to purchase the whole detachable plastic bit that is attached to the blade key?  I am assuming that the chip in the key is stored in the plastic part of the key, not the key itself?  I just wondered is it better to purchase the whole lot, or can the existing part off the used fob/key be re-programmed as detailed above?

Talking to a local locksmith, whom I use a lot, that operates from a van in a retail park, he reckons that the key cannot be programmed using the method above.  He wants £40 to program the key, but will cut a blade key for £6.  I would rather try the latter and the instructions posted in this thread.  

I was just wondering if anybody has any advice please?

Just in-case anybody does a search here is what I ended up doing.  The instructions that Louise posted above do work provided you get everything right.  You must get the correct 4 button fob, the same as your existing fob, either Visteon or Mitsubishi.  If you get the wrong one it will not work.  Mine’s a Mitsubishi, I bought a Visteon one first and it didn’t work.  Then I bought a used Mitsubishi one, was totally fine.

Regarding the blade key, I bought a blade key with the plastic part that mounts to it, that supposedly had the correct immobilser chip from Ebay, for about £14.  I got the blade cut by a local locksmith, the locksmith also told me that the above method for coding keys doesn’t work, and he’d charge £40 to do it, utter bs.

With my newly cut blade key, transponder at attached to my self-programmed fob, I tried the method that Louise posted with my 2 good keys, it simply did not work so I tried it again and again, but no use.  I then thought about trying the used Mazda transponder part of the key that came with the 4 button fob.  I simply used the above instructions, but when I came to code my new key, I simply put the new blade key in the ignition and held the base part from the from the used Mazda fob against it that came with my four button fob off ebay, and it worked.

So in summary buy the correct used 4 button fob off Ebay, make sure it is whole and the bottom part of the fob with the transponder is included.  Buy just a blade blank off ebay, get it cut to your  key.  You could ask the key cutter to swap the blade over to your new fob.  If not I bought a 1.5mm punch and held the keys in mole grips whilst I punched out the blade key pin.  Then with the complete assembly re-program the used transponder as described above.  

Maybe I got a dud blade/transponder off ebay, but I wouldn’t personally bother.  Its cheaper to buy a complete compatible item, and just swap out the blade.  Should cost you about £40-£50 all-in.  Worked for me anyway.

Bit of a thread revival here. I’ve done a bit of searching but cannot find an answer. My NC only came with one key which is an aftermarket thing, looks nothing like the original but has built in fob which operates the locks and alarm just fine. I would like a second key just in case anything happens the first and have found there seems to be different types as mentioned above. Obviously, the normal way of identifying which type I need by looking at the original is not an option. So, how else can I find out the information I need to buy another key without going to my local dealer?