Rx400h Key

[mobi]

Hi all, 

Our Rx400h only came with 1 master + 1 key shell only (no internals). 

So I bought an aftermarket key 4d67 from eBay and managed to programme the central locking with Techstream but the immobiliser will not programme. Getting error saying "the communication error occurred between the key and the ecu". I can only imagine that this is as it is not a genuine key. 

Has anyone actually managed to programme a replacement key for the Rx400h? It seems to be difficult to find a used rx400h key, do we know if a used rx300 key will work? Or any other known models that will work with the rx400h? 

Or if anyone has any other ideas that wont cost the earth. 

Thanks

Mobi

[Romasato]

I went through the same process since my car came only with a single key. After having lost it in a pub (and recovered after it was found) - I set on getting a spare key as I did not want the same stressful moments again. Lexus dealership prices for a new key I consider unjustified and hence decided to do it myself.

If you have the Techstream already - it is only a matter of getting exactly the same type of transponder chip and getting a new housing+blade cut.

1. Get your hands on Techstream software and OBD2 cable. Befriend someone working in a garage?:)
2. Get the correct transponder chip. Open up your original key and compare with the chip you got off eBay.
   • Do they look exactly the same and with the same code and same configuration of buttons? The code on the transponder is the firmware version of your ECU and has to match.
   • if it does not - back to eBay. I went by the code on chip and configuration of buttons (i.e. 3 of them on mine) and paid attention to the style of inscribed labels to match chip of my original key. You're better off looking for a used key as long you're sure the chip inside is the one you need. The casing with the blade won't be useful as it will be for a different car anyway and can be discarded.
3. Get a new key housing and the blade cut. Timpsons wanted to charge £35 for a housing + cutting. I paid £20 at some other key shop. Please note that very few key cutters will agree to cut a key if housing+blade is not provided by them - hence skip shopping for it on eBay. They say it is to provide a warranty or something. Mine's plastic housing has cracked after a year.
4. Insert the transponder chip into the new housing.
5. Register your key with your car's ECUs:
   1. Fire up Techstream, connect cable to the OBD2 port (located top of the driver's foot well, bottom of steering column).
   2. Insert your original key and get car into READY mode.
   3. Use Techstream menus (can't remember exact steps, dig around a bit) to register your key with two different ECUs:
      • Immobiliser
      • Alarm (door locking) system
   4. The Techstream software will guide you through the steps.

Hope that's useful - I wish I knew all of the above before...

[mobi]

Hi Romasato, 

That is some excellent information! Thanks very much. 

I shall check my keys and see where that takes me. 

Ill keep this thread updated. 

Thanks

Mobi

 

 

[sorcerer]

 

16 minutes ago, Romasato said:

1. Get a new key housing and the blade cut. Timpsons wanted to charge £35 for a housing + cutting. I paid £20 at some other key shop. Please note that very few key cutters will agree to cut a key if housing+blade is not provided by them - hence skip shopping for it on eBay. They say it is to provide a warranty or something. Mine's plastic housing has cracked after a year.

A lot of key cutters will refuse to cut blanks sourced from other places such as eBay, partly to do with what Romas says above, but also because a lot of the key blades are made from a very hard material and can cause expensive damage to key cutting machines. This guy on Ebay will provide a key with empty housing so that you can put your own transponder into it, but he'll also cut the blade as well, either from the key code if you have it, or from a photograph of your own existing key.