1998 SC400: Third Time's the Charm
#16
I wanted to retain my 95 keys because of missing the door locks, etc from the 99. I cut the key end off and attached it directly to the immobilizer ring, then stuffed it back behind the radio. I plan on adding a manual kill switch for extra security to kill the signal to the ecu.
I would recommend popping the cam sprocket covers off and looking at the condition of the belt. Also check for oil anywhere around the sprocket. The sprocket is the vvti gear, and it can leak oil. The "nut" on the front of the gear is actually a cover, and it has a gasket.
http://www.lextreme.com/forums/showthread.php?t=16485
In the linked zip, the Diagnostics folder contains a PDF which shows it being internal to the intake manifold (upper plenum), as part of the ACIS butterflies. No wonder I couldn't spot it anywhere on the throttle body or perimeter of the manifold. That looks like a design less prone to getting gunked up and needing servicing. Out of sight, out of mind.
The cats are different. The resonators before the mufflers are not straight through like the 92-97. They are larger rectangular units that actually 90 degree out to the mufflers. They did it for quietness over the old style.
Last edited by t2d2; 07-20-16 at 04:47 AM.
#17
Lead Lap
iTrader: (8)
That's a big bonus, to be sure. I got one Master and one Valet key with the '98, but the Master has a broken key ring loop on the handle, making it somewhat worthless. As soon as the title is in my name, I'll see about getting the key code from the Lexus dealer (inconvenient, being a ~3 hr drive) and then get a new Master cut, swap the remote/chip over to it, and set the original aside as a spare. That should cover my needs with minimal expense, considering the cost of new remote keys.
As far as replacing your current master key shell, I would recommend spending the extra money on an Eternity key instead of getting an oem key shell. I've broken so many keys over the years until I switched over to the eternity key.
There is also no need to go to the dealer unless you want lexus branded keys. I don't know about in your area, but where I live most lock smiths should be able to duplicate laser cut keys and program them now since this technology in the SC is considered out dated now.
#18
I ordered two key blanks for the '94 and figured it would be easy to get them cut locally. The main locksmith in town refused to do it (they won't cut keys of that style that they didn't sell themselves, which is way over-priced for non-OEM), and the other charged like $50 per key. Next time, I'll just order the key cutting service along with the blank from one of the eBay sellers with good feedback. I'd like to use the key code instead of the photo method, as the latter is bound to be a bit less accurate. I doubt the dealer will give me the key code until I receive the title in my name, though.
I haven't searched yet on documentation of how the key programming works... I take it there's something that reads the chip's code and writes it to the new key? I sort of doubt the locksmiths here have the ability to program the keys, given my previous experience. Would Toyota be able to or is it a proprietary Lexus process? I've got a Toyota dealership in town.
Let's say I get a new Master programmed and lose the original Master. Can another Master be copied from that new Master, or are copies somehow blocked from being copied?
Knowing now the importance of that Master key, good call on getting a full spare! One of the items in the car's dealership history actually is the ECU being replaced in '03 due to the customer losing the key. (I wonder if that means I've got an ECU outside the capacitor leakage window?) I'm guessing they only programmed one new key to keep the cost down, and that's the broken handled one I received.
I'm just using the Valet key for now and leaving the Master at home, so little danger of losing it. I've been impressed by the range of the remote, operating reliably from 50+ feet away, even from inside the house. The owner's manual says it should only be 3'.
I haven't searched yet on documentation of how the key programming works... I take it there's something that reads the chip's code and writes it to the new key? I sort of doubt the locksmiths here have the ability to program the keys, given my previous experience. Would Toyota be able to or is it a proprietary Lexus process? I've got a Toyota dealership in town.
Let's say I get a new Master programmed and lose the original Master. Can another Master be copied from that new Master, or are copies somehow blocked from being copied?
Knowing now the importance of that Master key, good call on getting a full spare! One of the items in the car's dealership history actually is the ECU being replaced in '03 due to the customer losing the key. (I wonder if that means I've got an ECU outside the capacitor leakage window?) I'm guessing they only programmed one new key to keep the cost down, and that's the broken handled one I received.
I'm just using the Valet key for now and leaving the Master at home, so little danger of losing it. I've been impressed by the range of the remote, operating reliably from 50+ feet away, even from inside the house. The owner's manual says it should only be 3'.
#19
Pole Position
iTrader: (1)
Will do...as soon as I find general layout & disassembly info on the VVTi engine. (Edit: I haven't seen indications of leaks anywhere yet.) I did find the answer to my earlier IACV question (does it exist?), at least:
http://www.lextreme.com/forums/showthread.php?t=16485
In the linked zip, the Diagnostics folder contains a PDF which shows it being internal to the intake manifold (upper plenum), as part of the ACIS butterflies. No wonder I couldn't spot it anywhere on the throttle body or perimeter of the manifold. That looks like a design less prone to getting gunked up and needing servicing. Out of sight, out of mind.
http://www.lextreme.com/forums/showthread.php?t=16485
In the linked zip, the Diagnostics folder contains a PDF which shows it being internal to the intake manifold (upper plenum), as part of the ACIS butterflies. No wonder I couldn't spot it anywhere on the throttle body or perimeter of the manifold. That looks like a design less prone to getting gunked up and needing servicing. Out of sight, out of mind.
The sharper angles with the rectangular resonator boxes is the part that I thought might be different if anything. I recall there being two layouts on the earlier 1UZ, with one looking somewhat like that, but I think that was the LS400 variation? You prefer the exhaust quieter, huh? I kinda liked removing all those resonators on the '94 and making it growl.
#20
Pole Position
iTrader: (1)
I haven't searched yet on documentation of how the key programming works... I take it there's something that reads the chip's code and writes it to the new key? I sort of doubt the locksmiths here have the ability to program the keys, given my previous experience. Would Toyota be able to or is it a proprietary Lexus process? I've got a Toyota dealership in town.
https://www.clublexus.com/forums/es-...apped-ecu.html
Don't mind that it's in the ES forum, its all the same.
One of the first things I did when I got my 95 was wire in my 96 wireless lock system. Was only 2 wires that needed to change, and I get better range and less BS on the key itself to break.
#21
Lead Lap
iTrader: (8)
I ordered two key blanks for the '94 and figured it would be easy to get them cut locally. The main locksmith in town refused to do it (they won't cut keys of that style that they didn't sell themselves, which is way over-priced for non-OEM), and the other charged like $50 per key. Next time, I'll just order the key cutting service along with the blank from one of the eBay sellers with good feedback. I'd like to use the key code instead of the photo method, as the latter is bound to be a bit less accurate. I doubt the dealer will give me the key code until I receive the title in my name, though.
I haven't searched yet on documentation of how the key programming works... I take it there's something that reads the chip's code and writes it to the new key? I sort of doubt the locksmiths here have the ability to program the keys, given my previous experience. Would Toyota be able to or is it a proprietary Lexus process? I've got a Toyota dealership in town.
Knowing now the importance of that Master key, good call on getting a full spare! One of the items in the car's dealership history actually is the ECU being replaced in '03 due to the customer losing the key. (I wonder if that means I've got an ECU outside the capacitor leakage window?) I'm guessing they only programmed one new key to keep the cost down, and that's the broken handled one I received..
#22
Lead Lap
iTrader: (8)
Once a component has that specific code, it will work. If you have a duplicate master key programmed (key word is duplicate) they should have the same code, which should allow the ECU to fire the car. With a little ******* on these forums, if you are a tech savvy person, there is a DIY write-up on how to put your ECU back into programming mode. It's advanced, but it can be done relatively cheap (say, 50 bucks in parts).
https://www.clublexus.com/forums/es-...apped-ecu.html
Don't mind that it's in the ES forum, its all the same.
https://www.clublexus.com/forums/es-...apped-ecu.html
Don't mind that it's in the ES forum, its all the same.
#23
The bottom end, and the accessories (how they mount) is pretty much the same as the old UZ, The heads are different, but nothing drastic with the exception of the cam gears/seal situation. It's actually alot easier to work on due to the front mounted throttle body and the lack of distributors.
I attached a exploded view of the vvti sc4 exhaust. I do like quiet.
I'd like to tell you that toyota could program it, but in reality, they seem to have the toyota and lexus brands split so far apart that you might have to go to lexus because the 1UZ was never in a toyota car here in the states.
Once a component has that specific code, it will work. If you have a duplicate master key programmed (key word is duplicate) they should have the same code, which should allow the ECU to fire the car. With a little ******* on these forums, if you are a tech savvy person, there is a DIY write-up on how to put your ECU back into programming mode. It's advanced, but it can be done relatively cheap (say, 50 bucks in parts).
The 98+ ECUs were better built, not really prone to cap issues as far as i'm aware.
That's common for a lock smith to not want to cut keys they don't sell... He also said if he cut my key and there was a mistake he couldn't offer me any type of replacement. After convincing him I was willing to take the risk of the key not working. I paid him $25 dollars and he cut my replacement key shell I bought on ebay. I ended up snapping that key in 2 months.
The programming method is a routine of lock/unlock, turn the key in a timed fashion. It takes some practice, but it isn't hard to do.
Any Lexus that uses the 3 button remote key is the same.
Each ecu can have a maximum of 4 keys programmed at any given time (2 remote masters and 1 valet from the factory, leaving room for 1 additional key). Once all 4 slots are filled, then you have to clear the memory and reprogram all the keys to start the car.
Lexus normally offers a reduced cost on ECU replacement the first time you lose all your keys as an act of goodwill. I think the requirement is that you have to pay for the 2 remote masters, and they'll install a new ecu and program it for you. This can only be done once during the life of the car though.
#24
Found the LS400 key programming instructions:
https://www.clublexus.com/forums/ls-...ml#post6103432
So, there must be an individual code assigned to each key's chip, in addition to the code they all share that the ECU is looking for? That's the only way I can see the limit of 4 keys working. At least it looks like adding a 5th just bumps the first one off, rather than having to completely start over.
Edit: Er, that only looks to work for remote keys, though. (Steps 'f' and 'g'.) Do Valet keys and non-remote Masters have a different process?
https://www.clublexus.com/forums/ls-...ml#post6103432
So, there must be an individual code assigned to each key's chip, in addition to the code they all share that the ECU is looking for? That's the only way I can see the limit of 4 keys working. At least it looks like adding a 5th just bumps the first one off, rather than having to completely start over.
Edit: Er, that only looks to work for remote keys, though. (Steps 'f' and 'g'.) Do Valet keys and non-remote Masters have a different process?
Last edited by t2d2; 07-20-16 at 10:13 AM.
#25
Lead Lap
iTrader: (8)
That's the same reason my locksmith gave. I wasn't able to get him to waive "liability" concerns, though. Man, it lasted only two months? I've had my eBay key for 2+ years with no issues. Then again, I hardly ever break anything of the sort. I've never broken or lost a key in my life (knock on wood).
You sort of lost me there... I saw the part about Max 4 keys in the owner's manual, but I don't understand the how or why. If the keys all share the same chip code, which I assume they must if they're being copied from each other, then how does the ECU differentiate them in order to only allow 4? Also, why would filling the 4th slot require clearing the memory and reprogramming them? That would effectively mean only 3 slots are useable... Clearly, I'm confused.
I only learned of this because when I bought my car I only had 1 remote master, and when they tried to make an additional remote master for my car they told me it was already full. Meaning the previous owners lost 3 keys or potentially 7 keys already.
Edit: I'm not sure if non remote masters and valet keys have a different process. I've only dealt with remote master keys.
#26
The weak point of the key is that it is a metal blade that is surrounded by thin plastic. It snaps where the blade meets the key shell. If you're aware of it and turn the key at the base (Blade meets key head), then it keeps the key from snapping, but if you're like me and turn the key at the top (where the key ring attaches) it weakens the key base and snaps.
You must have been writing that up while I posted the previous message.
I don't think the ECU copies the code, but it generates a code for each key.
The ECU can tell the difference between a master key and a valet key. A master key is the password to get into the system to add or remove keys.
Once you try adding a 5th key, then the ECU will make you reprogram all the keys, so that only 4 keys (max) can start the car. I only learned of this because when I bought my car I only had 1 remote master, and when they tried to make an additional remote master for my car they told me it was already full. Meaning the previous owners lost 3 keys or potentially 7 keys already.
Edit: I'm not sure if non remote masters and valet keys have a different process. I've only dealt with remote master keys.
Last edited by t2d2; 07-20-16 at 10:38 AM.
#28
Pole Position
iTrader: (1)
Found the LS400 key programming instructions:
https://www.clublexus.com/forums/ls-...ml#post6103432
So, there must be an individual code assigned to each key's chip, in addition to the code they all share that the ECU is looking for? That's the only way I can see the limit of 4 keys working. At least it looks like adding a 5th just bumps the first one off, rather than having to completely start over.
Edit: Er, that only looks to work for remote keys, though. (Steps 'f' and 'g'.) Do Valet keys and non-remote Masters have a different process?
https://www.clublexus.com/forums/ls-...ml#post6103432
So, there must be an individual code assigned to each key's chip, in addition to the code they all share that the ECU is looking for? That's the only way I can see the limit of 4 keys working. At least it looks like adding a 5th just bumps the first one off, rather than having to completely start over.
Edit: Er, that only looks to work for remote keys, though. (Steps 'f' and 'g'.) Do Valet keys and non-remote Masters have a different process?
On a side note, still good information to have , just not applicable to this particular conversation.
#29
Pole Position
iTrader: (1)
t2d2,
Here are a couple of pdf files I printed from Alldata to give you some more insight on the workings of the vvti. One is just an exploded view of the head (which has 90% of the changes), and the second is timing belt replacement.
If you need/want anymore stuff from Alldata, let me know, i'd be happy to send it to you.
Here are a couple of pdf files I printed from Alldata to give you some more insight on the workings of the vvti. One is just an exploded view of the head (which has 90% of the changes), and the second is timing belt replacement.
If you need/want anymore stuff from Alldata, let me know, i'd be happy to send it to you.
#30
These are in instructions for adding your keys to the wireless door lock system (since 96-97 were on a separate remote). This has nothing to do with the engine immobilizer. On a side note, still good information to have , just not applicable to this particular conversation.
I made some pretty good progress on the car the past couple days, swapping the LS400 calipers from the '94 to the '98 and the '98 front calipers to the '94, adding the stainless braided brake lines I bought after initially doing the LS400 upgrade, swapping wheels between the cars, and moving the axlebacks over to the '98. Plus miscellaneous cleaning.
I'm still looking into black wheels, but the flush silver is a huge improvement over the stock battleship chromies.