Master Keys Lost

[Keith's]

I bought a 2005 Lexus RX300 only supplied with 1 key & it wasn't a master as I found out, big problem if ever lost it or so I thought.

I wanted to blank out all lost keys & remotes to be safe then add new keys/remotes, being a 4D transponder inside remote this will be locked to the 1st car it's added to, so if deleted you can't re-program it to any car again.

I purchased a Lexus toyota smart key maker (online) to add new keys bought from Lexus directly, the keys being 3button remote with 4D transponder inside

With my only key in the ignition so not to blank it from the ECU IMMO

I pushed the smart key maker into OBD2 port under drivers knee holding the button until I heard beeping sounds, (THIS BLANKED ALL KEYS I DONT HAVE) putting ECU IMMO into enrollement mode ( looking for new keys needs 3 keys coded to stop this) I then removed key maker & was able to start & drive with existing slave key, the security light not working as should was telling me it's in enrollement mode, I took my 1st new key inserted into ignition for approx 8sec then my 2nd new key after 5 sec security light was off tested all keys started car ok, then programmed remotes to lock unlock doors, job done. Using a t300+ Obd2 tool I now Have 2 new master keys & 1 original slave key working on my car😃

[steve2006]

Welcome to the LOC.

This should be a great help to other members with missing master keys (a regular question on the forums)

Any more information on the device like a link maybe :)

[Keith's]

The toyota smart key maker is all over eBay £10-£25. I only used the T300+ OBD2 programmer to view info in the ECU IMMO to clarify 2 new master keys, also got this on eBay £139, the T300+ isn't essential but will be a great help as it gives you ECU fault codes to fix any faults (without trial & error) keeping costs to a minimum

[flumperboy]

Hi people . I just bought a RX 2004 . I only had one key and 2 blades .

One key looks like it's snapped from original key

2nd looks like summit from a shop ( no buttons .

And the only working key it huge .

I've bought a 2nd hand key of eBay . Changed the blade and put the 3 button chip in . All good but I would like a spare if it don't cost to much . I got a working chip . And blade but it needs programming to the car immobiliser and the 3 buttons .

Do I need the red toyota key programme tool

and do you think it will work on a 2nd hand chip . Thanks in advance :) (newby)

[Keith's]

Hi flumperboy it depends if your transponder is a 4D transponder if it is you can't add it to a 2nd car it's locked to 1st car it's added to, if you take it to an auto locksmith he will clone your working transponder & place it into your spare key, you'll need to code the remote to unlock the doors lots info on site about that, hope this helps

[Gliderpilot]

I didn't know there was a master key, I got three keys with my 400h two black and one grey, they said that the grey one was a valet key which worked the car but not the glove box. no mention of a master.

[Cymro]

I didn't know there was a master key, I got three keys with my 400h two black and one grey, they said that the grey one was a valet key which worked the car but not the glove box. no mention of a master.

Yes - me too with my RX300. So which is a Master? How can I tellby looking at them?

[flumperboy]

I've had a price from a local lock smith . £75 plus vat

[scudney]

The black is the master and the grey the valet

[Cymro]

The black is the master and the grey the valet

So that suggests that both black keys are masters?

Both my black keys (originals which I've had since the car was new) are showing signs of plastic fatigue, with cracks having developed near the blade. I've covered those areas with an epoxy resin, but that isn't a permanent cure. The time will come when I'll need to replace the keys - and I'd rather plan that task, and not have to do so in a crisis. Whilst I can get by for now (also have the grey valet key) and whilst it's unlikely that both black keys will disintegrate simultaenously, I need to replace them soon. And I now know that both of them are masters, either can be used for copying.

[Handsome_Hans]

Sorry for the bump, but this thread was informative. I have also lost my Master key, and only have a spare (gray) one left. It is a 3 button one, but the dealership confired it as a service key.

Does this also work for RX400h?

[sando63]

Hiya, I have just bought my first Lexus RX 400h, unfortunately only 1 master key,

how do I go about replacement without going to Lexus and getting charged a fortune,

PS I'm a dinosaur at this so the smart key info by Keith left me confused, (Keith how do you fancy a lovely trip to Sunny Staffordshire :))

Regards, sando63.

[Prince Bob]

On 26/03/2017 at 0:24 PM, sando63 said:

Hiya, I have just bought my first Lexus RX 400h, unfortunately only 1 master key,

how do I go about replacement without going to Lexus and getting charged a fortune,

PS I'm a dinosaur at this so the smart key info by Keith left me confused, (Keith how do you fancy a lovely trip to Sunny Staffordshire :))

Regards, sando63.

I called these guys when I needed a new key. www.themasterlocksmith.co.uk. They have very active facebook page if you want to message them on there instead.

They recoded existing key (remote buttons stopped working) and cut and coded a brand new key for £90 quid, took less than hour. The plastic casing on key was different. I was told the standard Lexus keys were prone to cracking. I was quoted £288 originally by Lexus....

[sando63]

Thanks Bob, I will take a look, very much appreciated,

Regards, Dave.

[djgrubber]

Hi All, has anyone tried a method mentioned by Keith? I am in the same boat and would like to find some sensible solution :(