When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
What's up guys. I recently bought my first LS, a 1990 LS400. One of my main issues is that the previous owner installed seats from a newer year LS400 (he thinks they're from a 93-94), but did not wire them up. I'm mainly concerned with the drivers side seat as it sits back a little too far at the moment, which was kind of a pain in the *** driving back 800 miles with the car after picking it up. Not to mention the telescopic wheel was stuck tilted up as well (which I eventually fixed using the zip tie method).
I have searched extensively on the wiring aspect of the seats. I have connected the White/Black and Blue/White from the harness to that of the seats and nothing worked, since that's what I read online for all basic motor functions to work. However when I jumped the seat from the car battery (ran a lead) the two same wires powered the lumbar support. At the moment I just want to slide the seat forward, that's it. The tilt on the seat is set to where it's already comfortable for me. Anybody have suggestions on which colors go with what, to just slide forward/backwards?
I have attached some pictures to show the four wires from the vehicle harness, and the twelve wires from the drivers seat harness. Thank you.
A little progress so far. I found out that I have to connect the Solid Brown and White/Black (Ground) together as one from the seat to the White/Black on the vehicle harness. The Blue/White (Power) from the seat goes to the Blue/White on the vehicle harness.
The seat motor functions worked fine after hooking it up to an 18v cordless battery, but did not work when connected to the vehicle harness. I played with the Green wire from the vehicle harness connecting it with the Blue/White from the seat, and barely heard the motor run, but absolutely no movement.
So now I'm pretty confused..
I was able to dial in my seat settings with the cordless battery, but not when directly hooked up to the car harness unfortunately.
Hey thanks for posting the diagram. It was slightly hard to make out some of the writing, but I think I understood part of it. I don't know if these newer seats have memory (my 1990 doesn't have memory buttons). The way I had it connected to that 18v battery to adjust the seat had all motor functions working (i.e. slide, lumbar, reclining, vertical,).
On diagram 2 it looks like White/Black would be grounded to ground point "I" (left rear pillar)?? As for the blue/white power I'm not sure exactly sure where that goes/ends at. I'm just trying to figure out how to wire these seats to the existing 4 wires that are coming from the harness under the seat. Otherwise I can probably just hook it up to a 12v source, right?
02-03-19, 01:56 PM
Unkown year seats in my 1990
