jimisbell

For my 2004 LS-430 I have two seemingly identical key fobs. They came with the car. when I bought it from the first owner about 10 years ago. One is perfectly normal and works perfectly. The second one came with a piece of duct tape over the battery compartment door. I never used it because it looked tacky.. Did not need a second key because my wife never drove the car.
After my wife died in the Pandemic I remarried and the new wife has become the master of the LS and I get the SC (Good choice I think). So now I want two keys.
I resurected the old key with a new battery door. It works just like it should including the remote operations. EXCEPT the remote ignition. If I put the fob "into" the fob receptical on the dash, it will turn on the ignition and all is well. BUT if I leave it in my pocket I cannot turn on the ignition switch. The other fob works fine in my pocket. Even the glove box unlocks with the slide out key. Just no remote ignition.

I at first thought the battery was weak, so I changed it. But the remote door locks and "PANIC" button both work properly! Any suggestions?

TarXan

I'm pretty sure the second key hasn't been paired to the ignition immobilizer. On pretty much every modern vehicle, there is an immobilizer that prevents you from turning the ignition unless the key is paired to the immobilizer. This has to be paired separately from the lock/unlock feature. I think you can pair it yourself if you have access to TechStream, but I've never done that before. I had this issue when I bought a new key fob for my ES330. I was able to get the key to remote lock/unlock the vehicle, but it wouldn't turn the ignition. I had to pay an automotive locksmith ~$100 to get the key paired.

I misread the post. I think @Loops320's answer below is correct. I just looked at the owners manual and found that the car came with 2 smart keys, 1 subkey, and the valet key. When I bought my car, it only came with the 2 smart keys, I didn't even realize that there were 2 different wireless keyfobs.

JffGRY706

probably a valet key car came with 2 smart and 1 valet key

Loops320

It's a subkey, they look just like a master but won't do any of the smart key tasks. Check your owners manual, differences are outlined there.

jimisbell

No, the valet key will not work on trunk and glove box, this one does

jimisbell

No, this does do all the remote stuff. only thing it wont do is start the car while still in my pocket. But does fine if I insert it into the slot.

jimisbell

Its not a big deal it just demands i put it in the slot. Thats ok.

Loops320

Will it pop the trunk button out in the lower dash? Can you open the trunk with the exterior button? If not, it's the sub key. The sub key will lock and unlock the doors, and start the car.

BigBoomer

If the Smartkey functions work (as in the doors unlock when you touch the door handle) then you should be able to start the car without putting the key in the ignition switch.
The SmartKey has nothing to do with the Remote buttons which still work even when SmartKey is disabled.
I suspect that it is a non-SmartKey or else the Smart side has not been programmed to the car, since only the Remote side and the Immobiliser which works when you put the key in the ignition switch.
Either that or the Smart part of the fob is busted.