On Saturday, 11/9/13, drove car from Brooklyn to Manhattan. Parked and shut motor. Guest arrived and I could not start car. Message was “key not detected”. Called service - they could not get car started. Did not respond to battery charge or anything. Key not working. Called tow truck and was towed to Brooklyn. Car still did not start after 8 hours. Next day, Sunday 11/10/13 went out to try to start car (did NOT lock car since key did not respond and did not want to get locked out). Tried to start car several times, car would not start. Message still “key not detected”. Monday morning called Toyota for tow to service department. Gave tow driver car key - and CAR STARTED. Toyota changed spark plugs (2 seemed sticky), checked battery, changed filters, checked fuel injection, compressor? - in other words THEY DO NO KNOW WHAT WAS WRONG OR WHAT HAPPENED. Car is working???
Ok, so we know you have a Toyota, but would like to know the model and year. But, the problem could be an intermittent failure of the chip sensor at the ignition switch. This sensor must read and verify the chip in the key before the security system will let it start. If it cannot read the chip, it will not start and display that message.
@DitmasPark
The first thing I would do is try your other key
In other words, if you get the “key not detected message” . . . immediately try the other key
If everything is fine with the other key, the “original” key may be faulty
Tell us if you don’t have your other key
As far as I know, all new cars are sold with 2 full function keys, so you should have 2, if you are the original owner
Yeah, need model and year. There could be a problem with the transponder coil that reads the immobilizer chip in the key, or the key itself. (assuming! that’s it’s a standard metal key, and NOT a “Smart Key”. If it’s standard, you probably just new a new transponder key cut and programmed by the dealer. Should cost around $55.00 for the key and 1/2 hour labor, which is $53.00 for us, less/more in other parts of the country. NOW, if it’s a Smart Key, you should change the battery first. If you don’t know hoe, usually the parts dept will just put it in for you. But, you remove the hidden metal key, use it to pry open the case (from the top slot, on the top side), and gently lift the circuit board out, gently remove it, and gently remove and reinstall a new battery. Now!, make sure you put it back together right. It’s kind of idiot proof, but don’t force anything together. New Smart keys can be pricey. Finally, sometimes even if the smart key fob works the doors, because of the dead battery in the remote, (or by pacing your keys by certain electronics!!!) you can accidentally erase the smart key code/or immobilizer code. Then, you’ll need to take it to a dealer and have them program it. All key codes are tightly secured by Toyota, and you need to be a Master tech (like myself) or higher to (or Service MGR) to get access to any re-seed or reprogram function, through Toyota’s secured website for dealer personnel.