Only one key fob

[dandreye]

Hi All,

Just got a nice 2011 CT200h that came with only one key fob. The trader says half of his cars incl much more expensive ones come like that and basically advises not to bother, and still for extra piece of mind I'm thinking of removing all but the current one from its "key memory" and getting a spare one. The local Lexus quoted it all done at ~£300-500 incl everything. Can I not buy a used one on Ebay and programme it into the "key memory" myself? If so where can I find the step-by-step procedure? 

Many thanks in anticipation!

D.

[m4rkw]

Definitely get a second key, if you lose your only key it'll cost thousands to fix.

These guys were very helpful when I needed a spare key: https://www.car-keys-online.com

[dandreye]

4 minutes ago, m4rkw said:

These guys were very helpful when I needed a spare key: https://www.car-keys-online.com

Hi Mark - thank you. Do you remember which Category you chose when ordering yours? I cannot see CT in the pop-down list of Models no matter which Category I choose.

[m4rkw]

My car wasn't listed there at all but they were still able to send me a key that worked when I asked.

[dandreye]

Doing some research on it all here meanwhile... could anyone please confirm if the following tool+software is good enough indeed (as some online videos I've just watched suggest) to add an already erased used key (i.e. brought to the brand-new state) from another CT200h into mine?

https://www.aliexpress.com/item/32793347357.html

If so then it makes the whole thing much cheaper: ~£80-100 used key + £10-20 erasing it + ~£10 for the tool+software above. 

[ColinBarber]

You can use Techstream, you need an existing master key. If you purchase the cable then you should use the official software and pay for using it on a timed basis here:

https://www.lexus-tech.eu/DiagnosticTools/Requirements/GTS

We don't allow the discussion of using the pirated copy you get with the cable on these forums.

 

Make sure you get a spare key that works for UK vehicles. For example a key from the US uses a different radio frequency and won't work with your vehicle.

[dandreye]

@ColinBarber:

Thank you: much appreciated! Why use a pirated copy if the official one is only EUR5/day.

Btw are the existing key and the missing one duplicates of one another or rather fully independent ones? Just wondering if I can also use the same Techstream software to remove the missing one from the car's memory, and if so how do I figure out which one of the 2 is which.

[m4rkw]

I think there’s a “forget all except this one” option

[dandreye]

1 minute ago, m4rkw said:

I think there’s a “forget all except this one” option

Perfect - thanks Mark. I'll then get the cable ordered. Looks like erasing a used key or just getting an already erased one is the only thing left to be taken care of.

[m4rkw]

I did once try to use techstream to add a key on mine but it didn't work. It wasn't a legit copy though and I had an aftermarket key for a JDM import with a different frequency.. so who knows why it didn't work. In the end I had the transponder on my existing key cloned by an auto locksmith.

[dandreye]

I thought I'd give it a try as it's so cheap and a good thing to have for various diagnostic purposes anyway. We'll see how it goes. 

[ColinBarber]

3 hours ago, dandreye said:

Perfect - thanks Mark. I'll then get the cable ordered. Looks like erasing a used key or just getting an already erased one is the only thing left to be taken care of.

The keys themselves aren't programmable. Each has its own unique rolling code sequence. It is the vehicles ECU that is programmed to accept the key.

[dandreye]

50 minutes ago, ColinBarber said:

The keys themselves aren't programmable. Each has its own unique rolling code sequence. It is the vehicles ECU that is programmed to accept the key.

Well not trying to argue as I'm completely new to this tech myself but the guy who explained how to add a smart key mentioned that a used one from some other car needs clearing/resetting first (which I called erasing above) before it can be added to any other car, and shows how to do it using CN900 Mini tool here... he clearly does something to the key itself and not ECU and says it increases its market value by ~USD15-20.

[Mossypossy]

I successfully cleared a used keyfob (£10) and then used Techstream (£40) to reprogram for my car.

Still have to get the new blade (£5) cut.

I have two spare fobs but they may be different from yours.

[200h]

the code that's erased must be like a pairing / identifier code that the car gives to the key

this will stop the rolling code from possibly unlocking any other car as the pairing / identifier code

and the rolling code must be the same on boths  sides

 

[dandreye]

@Mossypossy

 

Nice job ) What make/model are your spare ones and how much would one of them cost incl resetting if you were to sell it? Mine's a Tokai Rika B74EA with the "UK" frequency (no idea which one though). 

@200h:

Thank you for the clarification: makes sense now!

 

[Mossypossy]

One of my fobs will be £50 delivered. I had a spare that got lost in the post for two weeks. Bought two extras and then original turned up!

You would have to send it off to be deprogrammed IF it is correct for your car

 

[dandreye]

Which make/model is that and ideally also the frequency? Mine's a 2-button one (no boot opening button unlike in yours) but perhaps it doesn't matter. I do like the pricing but resetting (deprogramming) it may be a challenge, so I'll have to do some research here. 

[m4rkw]

It might be worth giving a local vehicle locksmith a call and asking them, lots of them have suppliers for aftermarket keys and they know all the programming stuff. If the price is right it could save you a lot of hassle, and potentially expense if something doesn't work. I got a spare key for my wife's old Nissan from car keys online, then called the local guy to come and program it. He said he could have supplied the same key for slightly less.

[dandreye]

Good point: thanks Mark. 

[Mossypossy]

13 hours ago, dandreye said:

Which make/model is that and ideally also the frequency? Mine's a 2-button one (no boot opening button unlike in yours) but perhaps it doesn't matter. I do like the pricing but resetting (deprogramming) it may be a challenge, so I'll have to do some research here.