JohnW420

1995 lexus LS400
First things first, obviously I know over a computer nobody's gonna figure my problems out. I'm looking for something who atleast knows a thing or two about the god damn electrical of these cars. Then I wanna know what steps you would take to go about trying to figure any of this mess out. Obviously I've checked all my fuzes and while none were burnt I replaced some with corrosion.

It all started with the blower motor, just one day stopped. I watched many videos read a lot of forums and could not figure anything out other then it was doing what it was suppose to during grounding tests. I tried cleaning all the ground points I could find with no success. After giving up and deciding I can live without heat until I can afford to just take it to lexus. But then all of a sudden the ignition or I don't even know what, stopped worked. Forever my radio and clock are turned on. I have a relatively new battery so that was fine I just unplugged battery overnight and it was ok. Now finally what happened yesterday Is the most confusing thing I've ever heard. Whenever I hit the breaks, the driver side rear window rolls down... Right how ****ed is that?!?

Can someone please give me some advice, please

Amskeptic

Yes. You need data by way of a wiring diagram/workshop manual. These cars have complex wiring and there is no way to successfully play a piano concerto right off the bat without good sheet music.

The problem with the brake light circuit energizing the rear window suggests a badly chafed wire loom or water damage or any number of possibilities. I pulled out the 67 page ladder wiring diagram for my 91 LS, and did not see any relationship whatsoever with the power window circuit and the brake light circuit. I did see an interesting division of electrical labor for the heater blower circuit because it has a controller circuit through the A/C ECU, a couple of resistor branches for medium and slow speeds, a power-sharing relay specifically for high speed, and the main heater relay. So, there is a HTR fuse in the front junction box in the engine compartment, but for some goofy reason, the CIG fuse (under the driver's kick panel) is utilized for the relay control circuits.

A good experienced Lexus mechanic who loves the challenge of electrical work, who has the layout diagrams and the ladder diagrams, who can tear apart your interior as necessary, and who can think clearly in the midst of chaos, could sort out your symptoms listed above . . . but it would be expensive if you had to pay for it,
Colin

timmy0tool

iTrader: (7)

since you have a sticker-bombed fender, that leads my mind to believe your car was slammed at one point.
the front tire could possibly make contact with the wiring loom under there thus shorting out everything on that wiring harness, causing your weird issues.

inspect the car for compromised wiring looms and harnesses!

JohnW420

It is lowered haha I just trimed the rust off fenders and never got around to getting flairs to cover.

But you fixed the break issue!!!! the back window no longer rolls down when I break. <3

but now I cannot get my drivers window to roll down which is no good at all D; if I could just get this id be happy

bradland

Symptoms don't really fit but it's worth considering...
https://www.clublexus.com/forums/ls-...capacitor.html

timmy0tool

iTrader: (7)

if you fixed the wiring, next is to check your fuses for any broken ones.