I drove the car and the hybrid light came on. I was able to drive to the nearest Lexus dealership, but after a couple days they said the code was P0AA6 and the information code was 526. They said i need a new transmission and the repairs would cost $5500. Im the first owner of this car and am very disappointed. Does anyone have advice or was in the same situation.

 

POAA6 can be as simple as a water leak. http://artsautomotive.com/water-leak...-lexus-rx400h/

Or something like this
https://lusciousgarage.com/blog/gen_...6_p0a92_p0a7a/

You probably will have better luck if you find a hybrid repair shop in your area. If it is the transmission, just get a used one for around $300 from ebay. There are tons of them for sale as they rarely go bad. The RX400h transmission is just a differential with an electric motor on one side and a gas motor on the other. They are much simpler than a traditional or belt CVT transmission.

Google your code for tons of good reading.

 

Show this to your dealer:P0AA6 / INF526DTC P0AA6-526 Hybrid Battery Voltage System Isolation Fault

Where does it say anything about transmission? Something's not right with battery/wiring. Those batteries tend to develop corrosion on copper buses connectors between the battery cells. Resulting in voltage drop and such.

Though I am REALLY curious to see a PSD - Power Split Device, that has TWO very expensive motors in it, for $300 - I do second smassey on taking your vehicle to a hybrid specialist outside of dealer. Vehicle is no warranty anyway. there are plenty of them quick wits guys that will scope your hybrid system and maybe even fix it.

 

Read this thread,
http://artsautomotive.com/water-leak...-lexus-rx400h/

 

Here is another video on possible problem.

 

Wow some great info here from top notch forum members.
As for the price on the transmission I do see several "used" aka "salvaged" transmission for under $500 https://www.ebay.com/i/112314452035?chn=ps

For some reason the salvaged parts are quite cheap for this car. I bought an engine for $350 (plus another $200 for shipping) to swap in mine. I am even tempted to buy a whole wrecked rx400h just for the spare parts..

Lexusrx40h I had an local mechanic install my engine ( I was very worried that they could not handle a hybrid but they did) the engine swap took about 30 labor hours (at least thats what they charged per their estimation software) After pulling the main fuse to the traction battery. The guy carefully labels all the hoses and connectors as he took the car a part and then just connected everything back the way it was and now the car is working fine so far.

I wanted to take my car to a hybrid mechanic in Chicago but they did not want to do an engine swap because it takes too much space/time on their lift.

 

P0AA6 code on my basic scanner. could it be this loosed ground on rear motor or water insode the battery?