Do you have any information on what the BCM controls? Just for my own reference in case I run in to similar issues.

 

I tried to reset the security system, but the only change was that the headlights now work. I still can't get the car out of park, and none of the cabin or dash lights work. Nothing works, no windshield wipers, no radio, no turn signals, no seat heaters or adjustments, etc. Does anyone have any further suggestions. I do appreciate this forum and what its members do to try ot help. Thanks to all of you.

 

Ok well you've learned a few things now. The next step is to read the DTC codes somehow through the OBD2 port under your dash on the drivers side. Find someone who has a reader or buy one. If you look you can find one for the price of taking it in and getting them to hook up. Of course its undriveable so you would have a towing charge also. I have one and have used it alot but I also have 4 cars so... Anyways that would determine if you have communications with the computer and it may reveal the source. Sounds like you have a complete power buss down right now but you need to figure out if it is the control side or the actual heavier current (supply) side. If that makes sense to you. Someone mentioned checking the fusible links. I'm thinking that's a good suggestion. Keep trying and don't give up until you have to because your chance of getting it fixed at the Lexus dealer is only as good as the tech they assign to it and if he sucks this could cost you a small fortune.

 

The problem is that it is a multiplex system so one electrical problem in the body control module or in the ECM can affect many functions the only way to know for sure is to run a Lexus scanner. The shop manual has some trouble shooting guides but after checking the fuses it says to make sure it's not a multiplex problem then once you establish that you can use the guides.

Did you check all your fusible links. If you gave it a surge that usually goes first