Welcome to JustAnswer.com! My name is DriveFast71(Ron) and I will do my best to answer all of your questions completely and accurately.
When the Check Engine Light comes on, the VSC and Trac lights are also set, which turns these systems off. This is a slef-preservation mechanism for the VSC and TRac systems, in case the reason the Engine Light is on can harm or effect these systems. So- fix the reason the Engine Light is on, and the VSC and Trac systems will come back online.
When the Check Engine light comes on, this is the on-board computer's way of telling you it sees a problem in one of the monitored systems. Unfortunately, there are litterally 100's of parts and sensors monitored in various systems, and to take a "guess" as to which part/sensor in which system is faulty, is virtually impossible. However, if you are not experiencing any drivability issues such as skipping, stalling, shifting problems, etc, then more than likely, the problem is going to lie in the EVAP (emissions) system. Very commonly, this could be a faulty, loose or missing fuel cap or even putting fuel in while the vehicle is running. Check the cap for any cracks in the rubber o-ring on the underside. Check the fuel filler neck for any signs of chips or debris. If these all check out, then the best thing to do at this point is to have the "p-codes" read from the on-board computer. These p-codes are what is used as a "starting point" for the diagnosis and will tell which part/sensor in which system has the fault. Once you get these p-codes you can more accurately and efficiently diagnose the problem and then make the repair. You can have these p-codes read FREE at any local "big chain" part store (ie. AutoZone, PepBoys, Advanced, etc). If you still need help after retrieving the codes, you can bring them here, and any of our Techs can walk you through the diagnostic procedure, and then even help you make the repair if you feel confident enough to try.
You will need a scan-tool. You can have these p-codes read for FREE at any local "big chain" parts store. You can even buy a "personal code reader" - do a Google search for "OBDII Code Reader" - and choose which is best for you...
I have an INNOVA 3100 code reader and have tried several times to retrieve codes but I keep getting an error code. Checked another vehicle with code reader and it's working perfectly. Thought I might need a special device to retrieve codes, don't understand why it won't retrive them from ES 350
Thank you very much for your help
Hmmm... that's odd. It's quite possible that the scanner you have does not read OBDII/CAN codes. You may need a "higher end" scan tool, like those used at parts stores. Toyota (Lexus) has an extremely efficient Trouble COde system, and if the Engine light is on... there's codes in there.