Leaky2014 - that's a big difference! By DIY are you saying replace the potentially faulty control/switch? I read about ECU failures but they seemed to show themselves by the light not coming on at all.
lx200inAR - any experience with either? Thinking really hard about pulling the trigger on this but would rather not dump a couple grand chasing these issues. Looks like LH mirrors are about $700 new for the entire assembly. Climate switches are about $200 new from Lexus, I'm sure they can be found for less.
I haven't had any issues with my mirrors. You generally don't have to buy a whole new mirror. Here's a YT video from a forum member on repairing one.
The light being stuck on for the climate-controlled seats does seem to be a strange failure mode. Usually when the ECU fails the light will not turn on at all. So it does lean towards being a switch first. There is an ECU you can check with Techstream that might give you a fault code to more quickly diagnose. Also, you can probably find a replacement switch on
eBay for pretty cheap (used OEM) or might be a good item to look for from Partsouq. Either way, if it's only the seat control, that's probably not a big deal to fix. Also, there's a thread on MUD where people are experimenting with replacing the seat ECUs with ECUs from LS460s, which used, are far more prevalent and about 1/10th the price.
All that to say, it would be nice to know if it's leaking or not. If it is, that would be a powerful bargaining chip. I got an okay deal on my LX (just before the prices ballooned in 2020), but i found out after i bought it the reason the dealership was trying to unload it was because it had a cowl leak that they couldn't fix. Luckily it didn't end up being that bad once I found it and fixed it. So, it worked out in my favor, but I certainly would have bargained even harder if I had known previous to buying it that it was leaking.
If it's in an open lot uncovered, you could try to go look at it after a rain. If it's not wet on the interior somewhere, there's a decient chance it's fine. But there's a lot of IFs in that scenario. If they will let you take it overnight, It only takes about 5 min to get to the connectors in question on each side (a little longer on driver's side) to check out the status of the connectors. I'm not sure how "cool" it would be to take apart something that you don't own that far, but considering the asking price for these things even though they are 15yrs old, I think it's at least justifiable.
All this to say, most of the common stuff isn't too bad to work on, as it's already had a lot of t-shooting groundwork laid out here in the forums. The cowl leak takes quite a bit, i think, to get into the electronics. It dumps water out into the passenger floorboard and doesn't really go directly into the body electrical plugs. A sunroof or windshield leak is harder to detect and more damaging as that water runs down the A pillar right into the plugs.
