2009 RX400H. 137,000 miles
I was driving on the highway when my car shut off and threw a Hybrid System Failure warning. I coasted to the shoulder and turned it off. Restarted it, and it runs, but I have a red triangle with a hybrid System error.
I have not hooked it up to an obd reader yet.
What are the first things I should look at?

 

OBD codes would be my first stop. Then search this site for like codes.

 

THe Hybrid cooling pump could be failing but without codes hard to say. Pump is located on drivers side on lower frame. That was the failure I experienced with my RX400h. It is an electric pump for the coolant that keeps the hybrid system cool.

 

It turns out the hybrid battery cooling fans are failing, which caused the battery to get warm. No harm seems to be done to the battery. I have kept the filters below the seat clean, so I don't know why it happened, but it is a relatively low cost repair.
​​​​​​Thanks for the suggestions.

 

Hi Gwirtel, from what I understand looking into this for other members, it seems like just age and time.
Happy for your success and simple fix.

 

I would say "cheap", not simple

 

I ended up taking it to a local Lexus dealer. My OBD reader only gave me the same info my dash light said, so I took it to a local shop, who told me they were unable to get any more info than my reader had. Lexus said the battery would not communicate with the system, so they needed direct access to it. The back seat and all of the other stuff covering the battery needed to be removed. After all that, that is when they found out it was the cooling fans. All told, it cost a little under $1,000. The first shop didn't charge anything.

 

I wonder if an app like Dr. Prius would've helped solve this issue.
It shows the battery temp at 3 areas, I believe.. maybe one of them would hit a high.
Who knows.

Glad you got it fixed. $1000 is hard to swallow but at least you can sleep at night, and that's worth more than $1000 in my book.

 

Yes, you can see the temp with this app. You can also setup the temp when fans will be turned on (earlier than by default from the manufacturer)

 

If I'm lucky, I will never need this information.
Thanks for the help though.