Lexus Smart Key Programming Failure
Good Evening All,
I am fighting with an interesting issue, a 2010 Lexs LS460 that will not complete the key registration. Let me start by giving a little history.
The vehicle owner lost her only key for this vehicle. A locksmith was call ed program a used replacement key. It is unknown what the locksmith did during programming. The vehicle was then towed to my customers shop where two locksmiths spent 8 hours trying to program the used key and then another 8 hours trying to program a new dealer key. Once again no one knows what they were doing to the vehicle. We were then called to program the key.
I arrive to program the key. The smart key erasure fails when attempting to start the procedure and the Smart key registration also fails on initial start. There are no codes stored and the vehicle will not power up. We are using the driver door switch cycling to wake the module up. Perform a data scan of the smart system and find that the data is intermittent and has some PIDs reading invalid. I recommend replacing the ID code Box and the Certification ECU per the Toyta/Lexus key programming quick guide.
I return after these modules have been replaced. The vehicle will power up now. I attempt to perform Smart key registration using both the classic and regular methids. Both methids have the same results. The key registration will start, recognize the key when it is held to the start button with a beep but when it is placed on the passenger seat the second beep never occurs and registration fails. It is the same with both keys.
I then check both keys using the TDB-003 Proximity Smart key tester which can check keys for signal and check the vehicle signals as well. Both keys show to be putting out the correct frequency signal for transponder, RKE functions and passive transmission. I then proceed to use the tool while attempting to program the key. I can see the vehicle send a signal and the key responds back getting the beep indicating the first step is complete. I then lay the key on the front seat with the TDB-003 and see the front exciter activate the key and the key transmitting over and over but it appears that the vehicle either can't see it or doesn't recognize that it is on the passenger seat. My hypothesis is that the vehicle knows the key is on the front seat by triangulation from multiple receivers.
I have attempted to test the transceivers but unfortunately Toyota only allows the transponder antenna test to work with a programmed key. Does anyone know which antennas are used for key location on the passenger seat or do you have any ideas of what the issue might be?
Thanks for taking the time to read this and for any help you can provide!!
Are you sure that there isn't another key inside the vehicle, perhaps the one that was lost?
Just a thought
That was my first thought as well. I've searched the vehicle from top to bottom for another key. I even went so far as to activate the transmitters and see if I could pick a signal with the TDB-003 from them like I can from the other two keys with no success.
Thanks for your help!!
If this car was in my shop I'd make sure I have two virgin fobs of correct part number (order new ones from dealer using VIN to be sure, if the circuit board inside the fob is slightly different than what the car expects it will not program to the car which is what appears to be happening).
You should not have to change any hardware in the car if you have Techstream.
Open both remotes and see if the circuit boards are the same part number/revision.
Did you do a Smartkey reset with seedcode/passcode via Techstream? If not, you need to try that next. If you don't have locksmith credentials you can purchase 5 passcode tokens from these guys for 25 Euros. weboctopus.nl/lexus-scion-to….php
Video here how to use their "calculator" youtube.com/watch?v=VnXCtu…
You could try Smartkey reset right now with passcode from Europe, then when registering keys select the appropriate box in Techstream. If you still get no completion after 2nd key, I'd order new keys before replacing modules in the car. Feel free to call me at … to discuss further I've done tons of Toyota Lexus key stuff. I even have the machine to the cut door keys by code.
A quick check for the oscillators is to use use a cheap am radio. Set the radio to 540 am and listen for an audible clicking with the radio sitting on or near the door handle and then on or near the console (this is where your room oscillator is located). If you hear the click it would indicate that it is looking for the key. If you hear no audible clicking i'd be looking to put a scope on the oscillator signal.
A known good vehicles audible cadence changes when the key is in proximity to the oscillator (either the exterior or the interior: aka "Room" oscillator.
There is another diagnostic procedure with more detail in TIS under: Vehicle Interior>Smart access system with push button start>Room oscillator does not recognize key.
Eric's point is also valid. It could be even your own key in your pocket while performing the procedure.
Thanks for the reply. The TDB-003 is able to show both the signals from the vehicle and from the key as present. It gives me signal strength and frequency as well. I read for a quite a bit yesterday but didn't see that article. I'll read that this morning. Thanks for your help!!!
The car doesn't care if the key is specifically on the passenger seat, it just wants it far enough away from the start button to not interfere. You can put the key almost anywhere else inside the car during programming procedure and it will work (if everything else is normal in the car and you have correct Fobs).
I've seen the symptoms you are describing quite a few times, it's usually because of wrong or non-virgin fobs.
Who supplied the fobs you are trying to program? If supplied by locksmith don't assume they are correct for that car. Also, you never said if you are using Techstream or some other tool. Aftermarket scan tools may not work as well as Techstream and/or allow a seed/passcode reset if that is required.
Thanks for the reply. One fob is aftermarket OE, most likely used and the second fob is dealer new but had locksmiths attempting to program it before I arrived. It is possible that since modules were damaged by the Locksmiths that the key is also damaged. I am using the latest version of Techstream for programming on the vehicle. I will obtain another new key fob and retry.
Make sure the new fob comes from the dealer by VIN. Tip: don't open the bag, you can program it without breaking the seal. If it doesn't work on your car you can try to return it. :) If the two known good fobs will not program do the seed reset then try again. Once a Fob has been paired to different car (it's now used) it cannot be paired to a different car unless you do a seed reset on the 2nd car or have the FOB virginized/unlocked to make it function like a new one.
Rick, I've got a lot of info for this system, I'm thinking it might be helpful for you. I'm unsure what the protocol for posting OE service info is. If you'd like to give an email address, I'll give you access, or if someone would let me know what I can and can't post, I can do that too.
I did have a question, is the steering column locking for you?
Thanks for the help. My e-mail address is …. The steering column is locked.
Sorry for the slow response. I just got a new key today, Virgin from Toyota, with the same results. I am continuing on to see if I can find something I overlooked. Any more suggestions?
I want thank all the people that took the time to respond to my request. A special thanks to Dusty Mills for providing access to his personal database on Toyota/Lexus smart key systems and to Paul Guzyk for the phone calls as well. The vehicle has finally been fixed.
The information on this system in the Toyota/Lexus service information is incomplete and what is there is very unorganized and , one might say, cryptic. Nothing in any of the symptom tables or repair information in SI leads you to the tuner module/antenna amplifier/door lock receiver as a possible cause. In fact the multiple part names used within this system are so confusing that in some of the information I found was a bulletin showing a chart of part names as they are used in SI, scan tool and parts catalog for each component in the system. Once I found a reference to the tuner module in a training document Dusty had, I started looking for it. It wasn't even in the Smart key system wiring diagram. I found it after searching multiple names in SI as the door lock receiver. The complete wiring diagram was under Door Locks. Once located it led me to the first of two problems in this circuit.
As I pulled the interior panes in the right rear trunk panel, I was hit with the overwhelming smell of acid or corrosion. When they were removed I found the area of the right rear trunk looked like it had been full of acid. The tuner module, radio amplifier and the entire wiring harness were covered in the reamins of whatever caused all this damage. Since the battery is in the front of the vehicle, I started putting the trunk back together to figure out where this came from. While I was doing this I found the jack and remembered that there was a gallon jug sitting on top of the jack on its side in the right rear corner of the trunk. The gallon jug was a half empty all makes/all models antifreeze container. It appears that the OAT antifreeze as it evaporated became quite corrosive. The bracket I am holding in the picture is the tuner bracket which is part of the case for the tuner board itself. If you look closely at the tuner board, you can see where the antifreeze entered the case and climbed up the tuner internal antenna for the trunk. In fact the lower left mounting hole in the board and the bottom edge of the board is white from the antifreeze.
After replacement of the tuner module, I found that the RDA wire was also compromised by the corrosion. A wire repair to that circuit finally allowed us to program keys and get the vehicle back to the owner.