I have a Gen 1 Lexus LS400 ('92) which developed the AC/clock LCD washout problem in cool weather that they all seem to eventually get and that Lexus ought to be ashamed of itself for not ordering a recall on.
It finally got on my nerves enough that I looked into a repair. I am NOT going to pay Lexus a penny to fix this for the reason stated above; I don't plan to reward inept design accompanied by a "we don't care" attitude.
Did a web search and found a California shop that sells rebuilt AC control units for ~$300 (plus ~$150 refundable core charge). I e-mailed Ken Weidemann there ( snipped-for-privacy@juno.com) a while back and did not hear from him for some time. Then he e-mailed me a few weeks ago that he had gotten a rebuilt unit in stock. Asked if I wanted it, I said yes and called his shop (877-778-6968) and ordered it. It promptly came and I just got done installing if a few minutes ago.
For instruction I used my Lexus Service Manual and a web site that gives instructions on radio replacement, a similar operation:
The walnut trim panel around the shifter is easy to remove if you use a couple of small flat screwdrivers to pry the panel up. The clips are not strong and you will not damage the walnut. Pry by inserting the two blades under the trim panel from behind the shift lever. No need to tape over them.
Removing the ash tray/trim panel started out as a major pain. Even with the shifter moved full back, there is little room to get a good grip. I ended up releasing the clips holding the ash tray/trim panel using a 90 degree bend pair of needle nose pliers that I hooked, in turn, outboard of the swing-out ash tray on both sides and then pulled, first one side, then the other. I doubt if I could have done it with just my hands.
I removed the A/C vents the way the Lexus manual says to do it. Covered a small flat screwdriver with plastic tape and then pried the vents out. Easy to do.
Removing the radio/AC cluster assembly should have been easy, but the four Philips screws holding it in were so tight that I almost stripped one of them. Lexus should have used hex-head screws here. Philips are inappropriate with such high torque.
To remove the A/C control from the cluster you need only remove the four round head screws holding the A/C control to the bracket that holds the cluster together and then remove two upper hex-head screws on one side of the bracket so that the hold on the A/C control is loosened. It slides right out.
Putting things back together was easy except that I had to rethread the four screws that had held the A/C and radio control cluster to the dash. They had been damaged in removing them and did not want to go back in.
The new A/C display works fine. The old core goes back for credit tomorrow.
The old one lasted about seven years and if the new one lasts that long I will be happy.