Lexus Troubleshooting Questions? Ask a Lexus Expert
Can you post a picture of the valet key and your normal key? When you insert the valet key into the ignition lock cylinder does the little red security indicator light stop blinking?
Do you have any of the key to try? They key that you have in the illustration is an immobilizer key you can tell by the dimple and the shank just past the end of the head of the key. If the light is going out that means the transponder ECU is recognizing the key code but does not explain why will not start the car unless there's something else going on.
Just to clarify the little red security light is going out the engine is cranking over but it will not start up correct? Do you have a code reader to check for malfunction clothes that might be set in the engine control computer? It may have nothing to do with the key itself there may be something else going on keeping it from starting.
Okay this then rules out anything with the immobilizer the immobilizer will not cause the starter to not engage. If it was an issue with the immobilizing system it would crank over but would not start up. Do you have any way to check for voltage to the starter i.e. do you have a voltmeter or simple 12 V test light? At this point are you just looking for general ideas as to what could be going on? Do you have somebody handy that can turn the key to the start position while you put your head under the hood of the vehicle to listen to a particular relay?