You have clearly not researched the subject on here, threads galore - the petrol versions, RX300/350 are not involved and the issue is resolved on the RX450 so far as appears to be known here. This remains an issue on the RX400, the cause is known - no physical space for a larger battery in the engine compartment. That cannot be cured, some people have used a different Bosch battery as a palliative.