I am a new owner of a 2012 RX450H and picked the car up 1 week ago. Since then, on 4 occasions the ready light has failed to come on so unable to start my journey.
The first time, I thought I was doing something wrong and then after several minutes suddenly all was well. However, whilst panicking over the situation I did wonder if the aux battery had gone flat but when it started dismissed this as pilot error.
But since then it has done the same 3 more times. Second time, very cold frosty morning go to start - no ready light! Get out the car, lock and unlock it, get in - all OK. Third time my wife was driving, she had used it earlier to go shopping locally with no problems, but some hours later the same situation to the point where she had to use our other car to collect me from work.
When we returned home, I tried and still the ready light would not come on. Tried both key fobs individually, and even touched the Lexus sign to the start button but still no ready light. I then noticed the LED reading light had been left on and after this was turned off and disabled the automatic headlights the ready light came on after about thirty seconds of pressing the start button, and away we went to give the car a good run.
Could this be as simple as the aux battery being low on charge, stopping the ready light showing, and then getting some sort of cross charge from the drive battery, just enough to enable it to work?
Or is it a more serious issue?
I'm planning to put my multi-meter in the car and check the standing voltage on the aux battery if the problem re-occur, but any advise would be most welcome.
Love the car to drive but this is making me feel anxious every time I go out to start it.