When I first got my 2004 S2000 (in 2013), I only received 1 key. I went to the Honda dealership and bought/cut another key (35113-S9A-A01) for $30. I never got around to programming it since they wanted something like $50-$100 to do it. I finally decided to do it and discovered you can do it yourself if you have the right equipment. I bought a CK-100 for ~$100 off eBay. You can find them on Amazon too. For the S2000, the CK-100 erases all the keys stored in your ECU and then adds in all the ones you want. You must have all keys present when you use it. There are other programmers (Honda dealer) that can just add 1 key without having to erase all the keys in the ECU, but the CK-100 is not one of them (for S2000 anyways).

How most immobilizers work? Your car keeps a database of allowed keys in the ECU. If it detects a key in the database, you can start the car. If it detects a key not in the database, it does not start.
Example 1: Your car's database has Key "A", "B", and "C" stored as allowed. You buy a new key "K". When you put key "K" into your car, it sees "K" is not in the database and thus does not start. You need to program the car's ECU to allow Key "A", "B", "C", and "K".
Example 2: Your car's database has Key "A", "B", and "C" stored as allowed. You buy a new key "N". You clone key "N" to contain the same data as key "A". Now you essentially have two key "A". When you put the new key into your car, it sees "A" and starts. You never had to touch the car's ECU because it already allows key "A".

Technical Aside: Most keys with immobilizers utilize passive RFID technology. Essentially, the RFID reader (your car) sends out an electromagnetic pulse. The passive RFID chip (your key) has an antenna that uses this pulse to power itself. It then modifies the pulse to send it's information back to the reader. This means that there is no battery in your key to power the chip.


CK-100 programmer. Attaches to your OBD-2 port and powers via standard 110V outlet.


This is the SW version on my unit. v99.99 is the most current version as of Feb 2017.


Choose Immobilizer from the first menu to program your keys to the ECU


Choose Honda USA


Select your year S2000, I chose 03-05 since I have an 04


The CK-100 operates on a "token" system. Basically, you can use the CK-100 till you run out of tokens. Each task you perform with the unit costs a certain amount of tokens. After that, you need to buy a new CK-100 chip for new tokens. A new CK-100 comes with 1024 tokens. I think this screen is saying that it will cost me 8 tokens to program the S2000 ECU. However, it actually only used 1 as you'll see later. I've read that it cost 8 tokens each key for a Ford Explorer so it definitely varies by vehicle.


Not sure if you need an existing working key for this but I would assume so. I used my existing working key.


I chose to see how many keys were in my ECU before I erased it.


3 keys in the ECU, yet I only have 1 of them.


Choose Erase All Keys to start the process


Select Yes to confirm


Enter the number of keys you want to program into your ECU


I entered 2 since I only have 2 keys on hand


From here on just follow the steps as you see on screen. I might have missed a couple of off/on steps here (following steps and photographing is too difficult for me I suppose, lol)










Here you need to look at your dash and see if the green key light is blinking or not. If it is blinking, it didn't finish correctly. Mine did not finish correctly the first time. I think I was too slow since I was taking photos. If the green key does not show at all, you are good to go.


Notice green key at bottom. (this photo was taken a day later to show the green key icon)


No green icon. Success!


If the procedure did not complete (Green key icon blinks), select No. You have 3 tries before it consumes your token. Select Yes once your are successful.


Only took 1 token from me to perform this procedure.


Here is a bug I believe. If you select yes, you can put in customer info (Last name, First name, vehicle info). However, after putting that info in, I couldn't exit the screen. I was stuck. I unplugged the CK-100. After I did that, only the first key I programmed worked. I then started over again and selected No the second time around. 1 more token used.


And that's it. I now have 2 working keys and a programmer to use on other cars in the future if I need it. Sure it cost more than the $50 at my local locksmith/dealer but it was more fun to do it myself. Assuming you use 1 token each time and pay $100 for the CK-100, this ends up costing you 9.8 cents each S2000 you program lol

 

awesome DIY bro! thanks for the heads up!

 

This is totally sweet! Finally definitive proof!

I'm in a similar situation with my other car, a 2011 Honda Fit Sport. Could this car be in the AK-100 database also?

 

I see 10- Fit so I think it is

 

This is legendary work. Thank you.

 

Legendary indeed!

Any plan on renting your unit out or programming other people's new keys? (and make your moneys back)

 

Hello, I am looking to buy a CK100 for my AP1 but I need to add a key to the CRV 2016 of my girlfriend. Could you tell me if it figures in the CK-100 please?

Thank you.

 

 

Thanks for immobilizer DYI. I was successful in programming my AP1 keys to a AP2 ecu.

I did an 2005 AP2 Engine swap into my AP1 2000 S2000. I also swapped over the AP2 Differential and Transmission. The goal is to pass smog at the state referee. Smog shops will not smog a car that has an engine change from 2.0 to 2.2 liters. The rules are that I have to have every smog related component from the donor car into my 2000 s2000.

The car runs fine with the AP1 ECU, but I did not want to take it to chance with the state ref. So I bought an 2005 AP2 ECU off ebay for $70 to swap. I also bought the CK100 from ebay, which took 2 long weeks to go from New York to California.

I spent over an hour trying to program the car, thinking the different year immobilizers were not compatible or that I have a dud CK100. I was ready by to give up, but by chance and luck, I was able to program 1 key.

The CK100 does not come with any instructions. It however has prompts on the screen for you to follow during the immobilizer programming sequence. If you follow the prompts, you'll be too slow to trigger the programming. I still am not exactly sure how to trigger the immobilizer rewrites, but what I did was press the keys on the programmer as prompted and then turn on or off the engine as prompted.. This method seems to trigger the immobilizer rewrites and save the keys to the ecu. I was able to go back and program 2 keys to the ecu.

Hope this helps those who wants to do ecu swaps. It is possible to swap different years 00-05 ecus.

Also, if you shut off the CK100 after the prompt "procedure successfully ended" and don't answer yes or no, you don't use up a token, but is able to program the keys.

 

Thanks for the guide! I attempted to follow this with a CK-100 borrowed from a friend and I keep running into ECU not found. Interestingly he also runs into the issue on his 06+. I was unable to get it to work on both my AP1 and AP2 I was unable to get it to work on my Honda Accord as well so it might just be a dud.