2007 GS450h need help the car wouldn’t go in ready mode

[acetfk]

Hey everyone,

I have a 2007 Lexus GS450h, and I recently ran into a big issue. we had extreme cold here in Minnesota (around -30°F), and my car was sitting outside during that time. After the weather cleared up, I went to work, and I noticed the car was acting weird—almost like the 12V battery was dying. The media system was super slow, but I didn’t think much of it and just went on with my day.

Then, suddenly, at a red light, the car wouldn’t go into Ready mode, and I had to get it towed. When I got home, I checked the 12V battery with a voltage test, and it seemed fine. I also tested each individual fuse, and everything checked out. However, the car still refuses to go into Ready mode.

Now, I do know that my hybrid battery cells have been dying slowly over time, but I never had any major issues before. Doesn’t the hybrid pack typically keep working until a single cell completely fails? Also, when I press the brake, I can see the hybrid battery charging through the energy monitor, so there’s still some activity there.

What should my next step be? Any advice would be greatly appreciated. Thanks in advance!

[Dean2]

Disconnect your 12V battery overnight. That will clear nay codes. Re-connect, very likely your problem will be solved. You may have to redo some of the driver selectable options, and auto open on windows, sunroof etc, but you won't loose anything important.

[acetfk]

Hi Dean Yes I did that, but no luck so far..

[Dean2]

So next step is to read the OBD port with a reader and pull the error codes. There is a diagnostic tree for each of those codes to work through. Post what codes and lights you get.