Hello,
So heres my issue. Every few months my gs-350 (2007) will not start. It will be completely dead.
Replaced the battery and its a month old and fully charged. Both terminals are fully clean. So i jump it and it starts. I bring it to the shop and have them check it, they say that the battery looks fine. They found a wiring issue with the computer and fix it. So today after i pick it up, the car starts fine but (and here is where it gets crazy). The key fob doesnt work. The power locks dont work, telescopic wheel doesnt move, the touch panel for the trunk and gas cap dont respond. Once i start it i can pop the trunk and gas cap. But the steering wheel still doesnt move in or out. So it will start and is drivable but the auxiliary power does not work once the car is off. So there are basic functions that are supposed to work once you turn off the car like the steering wheel, alarm, lights, trunk, gas cap, door locks. Those do not work at all once i turn the car off. Any ideas. Already disconnected the battery for 20 minutes and checked the terminals. Bringing it to the shop on Mon but checking with u guys fisrts.

Anyone have this issue. Thanks

 

I have a similar issue, I have been trying to figure out. 2007 Lexus GS 450h. It only happens on hot sunny days (I live in Florida). In the morning the car starts right up and runs great. Parked in the sun, many times the key fob will not work. I can see the red light on the fob lighting up, but no reaction from the car. A few minutes later the locks start working but no power will go to the starter button. I open all the doors and try to air out the car. Usually once the interior cools down it will start. Today I could not get it to start in my own driveway this afternoon. I went back this evening once it cooled down and it fired right up. I have tried the break light switch, fresh battery in the car and key fobs, replaced ignition relays . I have looked at replacing the fusible link block. No luck. Somebody has to know what is going on. There has to be a temperature sensor or relay that does not do well in heat. I am feeling your pain.

Please help... anyone...

 

I did countless forum reading trying to find some hints as to why I was having similar issues. Just picked up an 09 Gs350 and after 2 weeks of no issues I started having this issue where I would start it up, drive it and get to where I am going and the car would seemingly lose power. My key fob would not respond to the door to unlock or the push button on the dash would not let me even power on the car. It initially gave my wife the problem on the very first time she drove it. I had to go to where she was and fortunately I had my little jump box and it started after I jumped it. I assumed it was the battery so I got a new agm battery for it the next day. I drove it to make sure it wouldn't do it again and sure enough it did. Did some reading and read about the power source control module. the symptoms matched up so I figure I get one used, found one for about 150 shipped. installed it finally and it started up just fine. Thought it was fixed right? Same problem came back. I swapped the module again with the old one cuz the problem was intermittent. It didn't start so for 2 hours in the sun I figured I'd go through the wiring harness at the computers and power supply stuff , smacking relays and such to see if I could get power to the inside. Started leaning towards a bad push button but I knew it wasn't isolated to that. Got frustrated after sweating in the sun and tearing apart panels and such. Decided to shower and go catch dinner. I'd check it after to see if it was a "heat" problem and allowing it to cool off. After dinner i tried again and it didn't do any change. But while doing all that reading I remember someone posting a pic of the fusible link in the under the hood fuse box. I had already checked all the major fuse and it wasn't blown on any of them but in that one photo it pointed out a break on the very end which was NOT a fused portion of the link. SURE ENOUGH there was a hair line break on that part. You really needed to crack open that plastic cover to see that crack. I tried to solder it but it won't so I just made a metal sleeve to attached that part permanently. Not the correct fix but I wasn't going to spend 150 on a new link. If this happen on my GS, I bet it more prevalent on other Lexus/Toyotas too. So I wanted to come on a forum and make sure others had this to read so they can go directly to that point to check for themselves and not waste countless frustrating hours looking for this problem and spending hundreds like I do. Too many folks find fixes and don't contribute with follow ups as well.