hi, i am new to this , but i have a similar situation with my 1999 ls400. I had parked my car for 3 months and didnt disconnect the battery as i was hoping to start it regularly. needless to say that didnt happen and my battery died. i ended up getting a new battery. shortly after starting to drive it, the engine light came on. the computer was indicating door was open when it wasnt and then the battery would drain overnight and wouldnt start in the morning. i havent done any work to it other than change the battery. also it is showing rear tail light failure, but i think that was doing that before i parked it. the temperature gauge needle also just drops periodically. i have been told by my mechanic could be costly fix and might have to put the car to rest. the mechanic is a friend of mine, so dont think he is lying to me, i dont think he knows exactly what the issue is. any help.
