Toyota Repair: VSC, Trac OFF and CHECK lights on, camry solara, aamco transmissions

Question
QUESTION: My 2002 Toyota Sienna's VSC, TRAC OFF and CHECK lights are on again.  Last time, we brought the car to a dealership and we spent >$300 to fix it.  We were told that a computer chip was broken.  My Question:  What kind of computer chip this could be?  Is it possible that we can find the chip in an autopart store and fix the problem myself?  Thanks!

ANSWER: I have no idea what chip they are talking about, we don't replace chips only complete computers if necessary, at $300 this couldn't have been the case,I also have no idea what they replaced and charged you for. The best advise I can give you at this time is to try to have it diagnosed again and then let me know what the trouble codes are stored in the onboard computer, in most cases the check engine light is the root cause of the problem and if turned on will disable the vsc/trac systems so the first step is to find out why the check engine light is on. Most of the larger autoparts stores like Autozone and AAmco transmissions will get the code for you at no charge. Let me know what the trouble codes are that they find, have them write them down or get a printout then you can post a follow up and let me know and then I can help.

---------- FOLLOW-UP ----------

QUESTION: Followed your suggestion, I went to a local Autozone.  They have my car diagnosed and get the code for me.  The code is P0441.  I was told that the problem is some kind of vacuum leak.  I have no idea my car has a vacuum.  Do I need any further diagnose of my car?  Is this something I can fix myself?  Any advice is highly appreciated!

Answer
Toyota has issued a service bulletin for this code EG013-03: M.I.L. "ON" DTC P0440, P0441 or P0446: 00-03 Avalon, Camry, Solara & 01-03 Sienna (Revised),it recommends to replace a vacuum switching valve located on the air filter housing the part number is 90910–12209.