Thanks to everyone contributing in the discussion. I lost my key and successfully programmed a replacement as a new master key. Just to add another data point showing what works where, below is the info of the my vehicle, key, & programming steps.
Vehicle: 2008 Sienna LE (FWD)
Vehicle Manufacture date & location: 12/07 Indiana
Due to the urgency, I did not shop in the Internet. I bought the key from a local dealer for $48.50. The price includes cutting the key (but not programming). Dealer wants $150 to program the key which I declined. I personally do not mind on the $48.50 dealer pricing of the key as:
1. I know I got a genuine OE key (Toyota quality part).
2. Dealer freshly cut the key using data retrieved from vehicle VIN# (not duplicated from my existing somewhat worn-out key).
3. I got it the same day.
Information/identification of the key the dealer sold to me:
1. Toyota P/N: 89785-08020
2. Description: TRANSMITTER, KEY MAST
3. Has small dimple on the blade (per info found in the Internet, this is an identification for having 4D-67 chip; the right application for 2004-2010 Sienna and few other Toyotas).
Using the programming steps as shown in Youtube video posted by ovnisf in post #33
http://www.siennachat.com/forum/64-...-transponder-key-post1390689.html#post1390689, I programmed the new key on dealer parking lot; and at the end of the programming (step 6 below), I kept the engine running & drove home using the new key.
Programming steps:
1) Sat in the van driver seat with all doors closed but unlocked.
2) Inserted the original master key into the key cylinder (in and out) 5 times and left it there.
3) Opened and closed driver side door 6 times; left door closed on 6th time.
4) Removed master key from key cylinder. The red immobilizer/security light continuously lit.
5) Inserted the new key. The red engine immobilizer/security light blinked for a little over a minute, and then went out. Programming was pretty much completed as the light stopped blinking.
6) Started the van with the new key to confirm successful programming.
I noticed on earlier post by others that some of the steps (turn new key to ON during programming (might be part of step 5), and start w/ original master key (between steps 5&6)) are not needed.
Additional info I got:
When I asked how many keys total can be programmed to the vehicle, the Toyota part associate that helped me said the vehicle can only have 4 key max at a time.
Info copied from ovnisf Youtube page
https://www.youtube.com/watch?v=yoXdIS5UzFw:
Video shows steps on how to program your 4D Toyota chip key. This procedure does not work for all 4D immobilizer equipped cars. The models this has been verified to work on.
2004 - 2010 Sienna
2003 - 2009 4Runner
2004 - 2006 Camry
2004 - 2008 Solara
2004 - 2007 Highlander
2005 - 2005 Matrix
2005 - 2005 Corolla
2005 - 2010 tC
2008 - 2008 FJ Cruiser
If you don't see your model/year, you will require a locksmith/dealer. If your model is listed but you only have a valet key(gray color) you will also need a locksmith/dealer
Im not responsible if you can't get into programming mode.
Self Program method NOT working on:
2007+ Camry
2007+ Matrix
2007+ Avalon
2006+ Corolla
2007+ Tundra
2005+ Tacoma