100 series master key thread (2 Viewers)

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Have you by any chance measured the voltage of the (ksw) key unlock warning switch circuit?
I have been diagnosing an issue with my immobilizer circuit which ties into the KSW circuit. The workshop manual shows both 10-14 volts as well as 3-5 volts, I am measuring 3.6 volts. Clearly there is a misprint but which is right has yet to be determined since I haven't resolved the issue.

Cheers
I have not, but I’m planning to fix my hvac buttons later this week. I’ll go ahead and do the unlock switch assembly while I’m in there and grab the voltage for you.
 
I picked up an 06 LX470 and only have one master key. I've looked at the ebay link and it looks great but I'm confused as to what programming/programmer I'd need. I'm thinking I don't need to reprogram my ecu since I have a working master but I'm not clear on how to program the new keys?

Any help for this idiot would be most appreciated!
You'd need techstream. Refer to this post:

 

Have you by any chance measured the voltage of the (ksw) key unlock warning switch circuit?
I have been diagnosing an issue with my immobilizer circuit which ties into the KSW circuit. The workshop manual shows both 10-14 volts as well as 3-5 volts, I am measuring 3.6 volts. Clearly there is a misprint but which is right has yet to be determined since I haven't resolved the issue.

Cheers
I had 14V across the harness terminals.
 
I had 14V across the harness terminals.

I assume that's with the key out measured at the switch?

Looks like I need to find out why I'm getting 3.5 volts. Everything in line has checked out ok and the kws circuit is functioning as designed.
If I have ignition on and try to lock the door while open it prevents the locking.
 
I assume that's with the key out measured at the switch?

Looks like I need to find out why I'm getting 3.5 volts. Everything in line has checked out ok and the kws circuit is functioning as designed.
If I have ignition on and try to lock the door while open it prevents the locking.
That’s the open circuit voltage at the harness. Key in, ignition on, but with the switch disconnected.
 
That’s the open circuit voltage at the harness. Key in, ignition on, but with the switch disconnected.

So I went back thru my notes on the terminal pinouts and I mixed up my info. I have 10.5v at the kws terminal with key out.
The discrepancy in the manual is what concerns me. They call for 5 volts at the circuit with the key out and below 1.5 volts with the key in.
Like you I got battery voltage but with key out and zero volts with key in.

The Toyota manual is a mess
 
That’s the open circuit voltage at the harness. Key in, ignition on, but with the switch disconnected.

Thanks for taking the time to verify the voltages, greatly appreciated.

I have an ecu coming this week that I'll throw a virgin file in. I'm confident that my issues are in the ecm after the previous owner hired a lock smith to address his problems and fried more than just the immobilizer chip.
 
I was unable to program the fob on my ‘98 LC for close to 20 years. It ended up being a bad unlock warning switch assembly on the ignition. I was able to jump the harness and finally program my fobs. I ordered the part for $20 or so, but haven‘t installed it yet. 84052-33040

View attachment 3509501
Thanks for this, I will resume the key fob journey and definitely try this!!
 
hello all! I’ve read through this entire thread and just have a few questions pertaining to my key situation with my 03LC. When I purchased the vehicle it came with a transponder key ( no buttons ) and what I believe to be the valet key as it does not start the vehicle only unlocks doors. When checking the security light with the key that turns over the vehicle, it stays on for about 2-3 seconds. which leads me to believe this would be not the master key.

Stealership wants $280 for new key with fob plus $210 for program. I’m not really trying to go this route.

Local old school locksmith said they could cut A key and remove and program new keys to vehicle.

My goal is to obtain two new key fobs that remotely lock and unlock the vehicle and also keep the transponder key as a spare . Is this possible? Given I’m not sure that the key in my possession is a master key. I understand that I can flash the ecu with the techstream but I don’t have access to that.

I’m considering buying this oem fob new online and just getting it cut and programmed by the locksmith just trying to figure out the most viable solution here. I appreciate the help or feedback !

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Does anyone have part number for the two-button, international master keys? Also, is there a part number for the two, button transmitter only?
 
Hi all, just picked up an 01' LX.
Came with one and a half keys 🤣 one valet style key that starts the car and is the "main key", and the other key is the fob style...but it's just the blade, and empty shell. No fob internals. This just cranks the car, but no start.

Where do I start? It seems I'm going to need my ECU "virginized", but then, how do I add a new master and start from scratch?

PXL_20240509_003510534.jpg
 
So if security light goes off, without any blinking, one key increted into IG switch. Then that working key, is likely registered as master. If light blinks, it a slave. With master you can program more keys. Without, you'll need CPU flashed.

The blade with empty shell missing the door FOB, can't be used to start. The chip is in the FOB. So you'll need a FOB, to program and use that key in IG switch.
 
So if security light goes off, without any blinking, one key increted into IG switch. Then that working key, is likely registered as master. If light blinks, it a slave. With master you can program more keys. Without, you'll need CPU flashed.

The blade with empty shell missing the door FOB, can't be used to start. The chip is in the FOB. So you'll need a FOB, to program and use that key in IG switch.
2001, first of all, I want to thank you for your help in the community. Instead of watching Netflix before bed, since I've brought this LX, I I spend evenings reading through your thoroughly detailed threads. My rig, at 250k miles, will likely need everything you've done how -to's on.

As far as the key pictured -- it's not a master. After inserting into ignition the security light remains in for about a second and a half before disappearing.

So I get that I need a virginized ecu, and a new fob setup...but then how do I program a new fob to the fresh ECU? Is it just to normal in car steps outlined in here?
 
2001, first of all, I want to thank you for your help in the community. Instead of watching Netflix before bed, since I've brought this LX, I I spend evenings reading through your thoroughly detailed threads. My rig, at 250k miles, will likely need everything you've done how -to's on.

As far as the key pictured -- it's not a master. After inserting into ignition the security light remains in for about a second and a half before disappearing.

So I get that I need a virginized ecu, and a new fob setup...but then how do I program a new fob to the fresh ECU? Is it just to normal in car steps outlined in here?
FOB has 2 parts.

One part, is door FOB, which is a battery powered wireless (IIRC bluetooth) transmitter. I think you'll find how to program, in this thread. One way is through tech stream. The other is by a procedure of open and closing, switches, doors, ect. If not in this threads, search you find the how to. Also check my master thread.

The 2nd part of FOB, is imbedded immobilizer chip. It does not use or need FOBs battery.

Trick is, finding the proper FOB for your year. IIRC, there is 2 (possible 3) different frequency for both wireless door and immobilizer chip from 98-07 LX & LC.

I've only dealt with 03-07 LX. So you'll need to search for 01LC FOB info. Likely 98-02LC or LX the same. Possible 03-05 also.
 
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I guess it's my turn to ask a key question since I'm a new 100 owner and have looked through every page to help find the answer. I thought I had an idea researching this issue in another thread that it could have something to do with the immobilizer chip but I can't find it anymore.

First of all I have a 2007 Land Cruiser with one working master key. I received a second OEM key when I bought the truck that was dead, and have since replaced the battery in it. It's a 12BBT, which is for my year truck to my knowledge from this thread, and it unlocks and locks the truck perfectly fine. However does not start the truck. It's cut, and I've tried the normal sequence of events to try and program the immobilizer to acknowledge the key but since viewing this thread there is post #46 which I am going to attempt, and I'm going to order a TechStream cable if that doesn't work.

My question is could the immobilizer chip gone bad? Is there a way to verify it's the right chip, and I'm also curious where to locate the 4d-68 designation on the key fob, because I do not see that information anywhere inside the fob.
 
If it will not program it seems likely there is something wrong with the key chip. My $.02. Have you successfully programed other keys? There are multiple procedures and it took me a while to get the right sequence one working for my 2000.

I have a sort of similar issue with one that will not unlock anything remotely but I was able to program it to the immobilizer. I think the transmitter is shot. A new battery lights up the red light when a button is pushed but it will not program to the doors.
 
If it will not program it seems likely there is something wrong with the key chip. My $.02. Have you successfully programed other keys? There are multiple procedures and it took me a while to get the right sequence one working for my 2000.

I have a sort of similar issue with one that will not unlock anything remotely but I was able to program it to the immobilizer. I think the transmitter is shot. A new battery lights up the red light when a button is pushed but it will not program to the doors.
I have not programmed anything else. The procedure I tried was the tlcfaq procedure for 2003+ but it doesn't seem like anyone has had luck with the procedure for new keys. I think techstream will be my best bet in figuring out the history of keys and ultimately what I'm going to need to figure it out, but I just wanted to verify my immobilizer chip was the correct one.
 
Looked thought the thread and have not found a solution for my issue yet. I have an LX470 2002.

I think I only have a valet key (only have 1 no fob key, but it does unlock everything including the glove box and starts the car). However, I have yet to see the security light at any point when in the car, outside the car, or putting the key in.

All I want to do is program another key in case I lose it. I do not even want a fob. Anyone know what might be up?
 

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