I tried searching but was unable to find any information about this issue; if I missed it please point me in the right direction.

I have an '08 600h and the cluster has started "rebooting" when the car is first turned on. What I mean is that when the car is switched on, the cluster goes through its startup sequence, needle sweep, etc., but then turns back off and darkens again. Sometimes it will do this through as many as three or four cycles, and today it even did it after a minute or two of driving. The car continued to run and drive fine, so the issue appears to be completely isolated to the cluster.

It's cold here in Utah, hitting 20s/30s overnight, but we're not even to the coldest part of the year yet. Given that the problem is limited to the initial few minutes of operation, I don't think loose connections are likely. I suspect some component(s) on the cluster boards, but I have no idea which. I'm hoping that someone else has run into this and might have more information.

I'm new to the Lexus brand, but coming from BMW and Audi I'm familiar and comfortable with CAN concepts and modifying programming. On one of my BMW's I modified the mileage of a used cluster to match my cluster for a swap, so I also have a programmer with clips for in-place reprogramming, if it comes to that.

 

It anything, it looks to me as a bad connection or a bad solder joint. I would remove the dash and inspect connections, clean if necessary. Did you get any error codes?

 

This may be an indication that your Starting Battery Is near the end of its life.

 

+1 Battery going out. Does the car start without any issue?

 

No error codes (I don't have an interface for Techstream, but I have an Autel dealer-level diagnostic tool), and the car starts without issue. The lights were inadvertently left on overnight a few days ago, after which it wouldn't start, but as soon as I jumped it the car started without issue. I then hooked it up to a power supply and charger used when flashing modules, and there's been no issues since.

I hear what y'all are saying about the battery, but it reads 12.3V with the car switched off, and 11.65 to 11.75 with the car on but not running. If I read this correctly, the battery is also only a little more than a year old:



This leads me to believe that it's something internal to the cluster, as mentioned, like a solder joint or capacitor. I'm installing a Grom VL2 in the coming days, so maybe I'll also pull the driver-side bits out to take a look.

 

Two things to tell you.

11.75V is too low when the engine is not running.

If the battery is fully discharged it needs to be disconnected from the car, fully charged, tested and reconnected. Same applies if the car is jump-started.

 

And that may well be it. After a few longer drives at interstate speeds I haven't seen this happen again, so it may be the battery was simply undercharged. I've got plenty of trickle chargers for my motorcycles, so I've got the LS battery hooked up to one today and I'll see how it goes over the next few days.

 

After parking the car outside one afternoon and coming back to it the next morning, the problem persists. Right now we're in the 20s during the day and teens overnight, so it highlights a weak battery right quick. I also started the car in the dark last night after sitting for a while and I realized that the internal illumination also isn't coming on. At this point the battery does seem the most likely culprit.

A previous owner had the battery replaced at a local dealer just over two years ago, so I can get the OEM battery from them at 50% off. They had to order it since they don't have any on hand, but tomorrow I should be able to swap it out and hopefully resolve this.

 

OK, still happening even with a new OEM Panasonic auxiliary battery. I've tried charging it both on and off the car to no avail. The charger is rated to 75A continuous duty for use when programming modules so it can definitely handle charging in either situation.

The panel illumination continues to also flicker on and off at the same time, so it does for sure seem to be voltage related. As far as I've read and know, there's no alternator but instead an electronic transformer to step down the traction battery voltage to approximately 13V for the auxiliary battery. Does this fail? I know BMW's have a specific 12V battery sensor to monitor voltage, but I haven't seen any mention of something similar for the LS. There's not much in the FSM about troubleshooting the auxiliary battery so I'm very open to feedback...

 

Thanks to @jmcraney in another thread I'm pretty confident this is the result of battery drain from doors' states not being read correctly by the car. I was able to prove to my satisfaction just now that my driver door switch at least is bad. I can get the door to go between showing as open or closed by just jiggling the switch up and down, and the interior lights don't come on when the door is opened from a "sleeping" state. If I jiggle the switch a bit I can get them to turn up.

The switches are cheap enough that I've ordered a full set of 4 from Amayama to replace them across all of the doors.

 

Do you have a link for those switches?

 

Amayama Catalog

84233 in the diagram is part 84231-50190; the same part is specified for all four doors.

 

I have exactly the same thing happening but mine is slowly getting worse. Now it doesn't need to be as cold for it to start the cycle. I've replaced my battery and replaced some corroded parts with no improvement. Please respond if the switches make a difference. I don't think my switches are the problem but hopefully I'm wrong. Thanks!

 

do you know how to test the switches why are you guessing ?

 

I haven't replaced mine yet, but I'm 100% confident that it's the cause in my case. The test is simple; go for a drive, then open the driver's door. Watch the instrument cluster to see if the "door open" light comes on and the interior lighting turns up. If it doesn't, try just barely tapping the switch at the rear of the car-side of the door frame. In my case, I don't even have to apply inward pressure on the switch; just wiggling it up and down causes the lighting to flicker. You can repeat the same procedure for each door, but I'm getting switches for about $6 a pop so I just bought a set of four.

The car has different power states and doesn't "sleep" as long as a door hasn't been opened after shutting off the engine. A good way to know that it will sleep is to listen and feel for the electric steering column lock. If it engages, that confirms that the car has detected the open door and is preparing to sleep. If it doesn't, wiggle the switch until you hear the steering lock actuate. Since I've started paying attention to this and following this each time I turn off the car I've not had a repeat of the issue.

EDIT want to call out again that jmcraney suggested this as the issue. I would never have thought to check the door switches in connection to my cluster problems.