I'm a new member on this forum. I just bought a 97 LX450 with about 72,000 miles. So far, this forum has been very helpful. I am a victim of the notorius "little white cap" problem with the power seats. I bought the LX knowing that there was an issue with the driver's side seat, then after the purchase I discovered this site. I checked for the missing cap, and sure enough, the cap was missing. So, I looked on the passenger's side, no cap there either (and surprise surprise, the passenger side seat didn't work either). Fortunately, I have a neighbor down the street that has a 97 LX so I asked about their seats. Their passenger side seat does not work and the Lexus shop graciously disconnected the power to the seat for them (WTF?). However, their driver's side seat worked and had the cap. So they let me borrow the cap and of course it took care of the problem with my seats. Now for the parts dept. I e-mailed the parts department of my local Lexus dealer along with a complete explanation and pictures of everything. As others before me have already discovered, they apparently do not sell the part but rather you have to buy the entire housing (I am still working on confirming part numbers, etc. but I think this will end up being part # 72206-30040 (A044 Housing subassembly) as others have already reported here). Price tag is about $90.
When I had my neighbor's white cap, I measured the part. O.D. is 0.50" and the bore in the middle is 0.24" and the length is 0.38". I managed to find a nylon spacer at Lowe's that was advertised as O.D. 1/2" (measured 0.49"), bore 0.257" and length 1/2". Well, it was close but not close enough. When I pushed the bushing in the seat, it tried to work but would occasionally skip on the side where the cap installs. I assume the tolerances are just very exact. I also tried a bushing that had the same outside dimensions, but a bore of 0.194". It would not fit over the shaft so I drilled it out with a 15/64 bit (~0.234"). Now it fits over the hole but since I just had a hand held drill the bore was a tiny bit off center, and again it only works sporadically.
At this point, I think I have no option but to buy to whole housing at $90. I'll probably only buy one and use the cap to set the passenger's side all the way back and then leave the cap on the driver's side. I'm 6' and my wife is 5'2" so we definitely need to be able to adjust (of course, if I had no cap maybe she wouldn't drive it.... I better not go there).
Not that it would do any good, but I also sent a complaint to Lexus corporate about this. The spacers at Lowe's were 46 cents each. It kills me to pay $90 to get this part.
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