I just got my 2004 GX 470 back from the dealer after my 50K service. The negative battery post had leaked and corroded the wiring harness. The battery and harness were replaced. I noticed tonight that when the engine is not running and the key is in the ON position the A/T Oil Temp, Battery, Oil and Check Engine lights are on until I start the truck and then they go off and stay off. I had never noticed this before. Does anyone know if these lights are supposed to on in that situation?

On a side note I had to take it to two dealers in Dallas. It took Sewell Lexus and it took them a week just to do the service, and then they refused to honor the CPO to replace the harness. After a huge hassle with Sewell I had to drive it to Park Place Lexus in Grapevine to repair this. They replaced it with no problem.

I havent driven my GX in a while, but I do remember that those lights do come on during the "ON" position before you ignite the car. I'll check later with my 4Runner since it has the same characteristics. I think you should be fine.