The driver's side is really all we care about. This is because it controls the passenger side too. If the passenger side fails who cares, worst case is you can disconnect it with no ill effect (AFAIK).

The symptom of impending doom or failure of these climate control button is "stickiness" or "stuck". What I mean is if you are pressing the up or down button and it seems to stick/stay depressed and keep going even a few more times than you hit it then the path to destruction has started . Seriously it gets worse and you just think "that's annoying" but go look at the Lexus forums and what I say will make sense soon.

The next step is that the button gets totally stuck, it cannot be fixed or unstuck. Why is that a problem? Because if it's summer time and it sticks on max hot that is a problem. Conversely in the winter if it gets stuck on max cold that sucks too .

With the Celsior being RHD you cannot plug and play the LS430 button. But as a quick fix I did order one. It will plugin fine to the harness but cannot be mounted since it is backwards (eg. it is like trying to mount the passenger control side on the driver side or vice versa it won't fit). But you can at least plug it in long enough to set your desired temp (the button itself pops out as a unit as you'll see below with a small eyeglass style flathead screw driver).

The long-term fix was to order a used driver side control from Japan (I also found some from Lithuania on eBay).

The original part# is 87190-50030