Hey folks, I just bought a 95 LS400 and have been trying to solve this problem for days unsuccessfully, so I thought I'd join a forum and try to enlist some help. Tail lights and license plate lights do not work. Tail light failure indicator is on. Turn signals, brake lights, etc. work fine. Changed bulbs and checked fuses. Seems to me like it's probably a ground somewhere, but I haven't been able to locate the problem. Any suggestions?

 

check ALL the fuses (ie-test, not just visual)

 

I am also experiencing issues with my tail lights as well but also let me share another issue. Before my tail light issue, I was experiencing issues with my dashboard. There were no lights and speed needle was not responding while driving. After a couple minutes later the dash would flash, needles would jump and then we are back to normal operation. This has happened 5 times thus far. I thought it was just some weird experience but not much of a big deal sense the dash would operate after.

I guess I was wrong.... Now my taillights are not working. Whenever I put my foot on the brake, the brake lights come on. But when I go to power on the lights by the switch (headlights and rear lights) only the headlights will come on. I've even tested the reverse lights and they work with the light switch on or off..... I decided to check all rear light bulbs and did not find any bulb blown... Not to mention I replaced them all 2 months ago. Next, I checked the fuse on the driver side panel but I did not see any blown fuse but I will verify tomorrow if there is a bad fuse or not when my dad test with his fuse testor. Besides that I do not where else I should go. It's weird, because this morning they worked when I started the car up to warm the engine. I came back and my rear lights were not working but the front lights were. I don't understand....

I did do some research and notice the following article:
http://www.lexls.com/tutorials/lighting/bulbout.html
How to Fix Strange Dash Lighting & Brake Problems
1990-1994 Lexus LS400

My 4 questions are:

1 - Has anyone experience the same issue as I am? When you press the brake pedal you're rear lights come on but when you turn the light switch on, the rear lights do not come on?

2 - Has the LexLS lighting and brake problem fix worked for anyone?

3 - I've attached a picture of a wire I found under the driver panel, does anyone know where the wire should be connected? When I went to check the fuses, I notice this wire was not connect....

4 - Please let me know what you may suggest on things I should check?

 

Just wanted to let everyone know I solved my problem.

My issue was; if I turn on my lights, the front lights would work but all of the back lights would be off. So I check all fuses but none were bad. I checked all my bulbs but none are bad plus 2 months ago I replaced all bulbs on the car so I knew if wasn't the bulbs. I checked all wires running from the lights but none were bad. I even did check the wire harness running from the left side of the trunk aka

http://www.lexls.com/tutorials/lighting/bulbout.html

but that did not solve the problem. Being a I.T. expert I knew there had to be some circuit that had multifunction. So I went to the junk yard and grabbed the ''lamp failure'' device and replaced mine with the one at the junk yard and now the back lights are working.... So if anyone has a issue just as I am, be sure to check you're lamp failure device which is located in the back trunk on the driver side near the taillight wire harness.

Thanks!

 

lje87=if you follow the trunk harness down the drivers side hinge to the body it should plug into a lil square black box that attaches to the body harness. In my experience either the harness or the modulke are bad. If it is the harness it is visually broken wires. In your case i would remove the "lil black box" and open it(very easy) when you get it open you will see a burnt solder joint trace the circuit visibly on the board and you will see where to install a jumper wire to repair the board-keep us posted

 

Hey all you Lexus fans. I have a '91 LS400 and I am having the same tail light problem. The head, parking, fog, brake lights, and turn signals all function properly but the tail lights and the licence plate wont work at ALL. I've changed all the bulbs within weeks. And I've tried to replace the lamp failure box, no luck. And all the wiring is fine. I was wondering if anyone had anymore suggestions? Any are appreciated. Thanks

 

Just wondering if you or any fellow members knows where I can find the part number for the rear tail light failure relay for my 94 SC

 

have you got a volt meter?see if you have power check bulbs,take out rear lights check and clean ground wire.