Has anyone found water in the battery area? Couple time my daughter’s car wouldn’t start because of a couple inches of standing water.

is there a sunroof drain tube going back there?

 

Welcome to CL. You need to identify your model and year as the hybrid 450h has the 12 volt battery in the rear and the 350 has it under the hood. I was going to move it to the hybrid section, but a hatch leak is universal.

Assuming you have the hybrid the water could be from a few different sources.
The rear sunroof drain is one because the tubes run down each side of the rear hatch and do get clogged.
Or the rear hatch seal has an issue allowing water in, or the hatch is not aligned properly.
I think There are removable rubber drain plugs in the bottom under the tire or elsewhere.

See post 5 in this linked thread as it links you to threads regarding clearing the rear sunroof drains https://www.clublexus.com/forums/rx-...ring-tool.html

This thread also discusses the rear tubes https://www.clublexus.com/forums/rx-...ain-tubes.html

These threads discusses solving a rear hatch leak

https://www.clublexus.com/forums/rx-...ved-maybe.html

​​​​​​https://www.clublexus.com/forums/rx-...ate-motor.html

 

Yes it's a RX450

 

First check the rear sunroof drains following the instructions in the linked threads above.

 

Has roof rack?
If so,there are reports of rain leaking in at mounting point holes.
Seal with waterproof adhesive