RA40

iTrader: (6)

Some past threads that may be of help:

https://www.clublexus.com/forums/ls4...t-92ls400.html

https://www.clublexus.com/forums/ls4...lb-socket.html

A friend's Acrua Integra was doing this, what it wound up being was one bulb was a single filament type that was mixed in with a dual type, when the brakes were applied, it would light up but the other tail lights would go out.

geoprz

Thanks! It ended up being that little black box. It was obvious once I opened it that it was the fuse.

steve2006

Check the bulbs on the top and bottom sections of the outer clusters, they need to be double filament bulbs one for the tail lights and the other for the brake lights, looking at your picture you have only single filament bulbs fitted in there or the bulb holders are only single filament, there should be 3 wires on each one.



That unit has drawn some serious over currrent, you need to find out why before replacing it or you may destroy a replacement.

geoprz

Can I get a picture of someone's tail lights on but no brakes preferably the same style of lights

Yamae

A picture may help you some but I don't think that can fix your problem. Those aftermarket products are not always the same and you cannot expect the equality. Also the quality is terrible. Yours may have unique / wrong wirings to outer side bulbs or bulbs are not correct ones.

I suggest you to act more with engineering minded method. It has been already 5 months since the problem has started. You are still struggling without succeeding to fix the problem. You must be busy or your way of fixing method is not good enough for the past 5 months.

If I were you I would quickly check bulbs and trace the tail light wiring lines and check the connection to bulbs using at least a circuit tester. In addition to that I fix or buy another sensing unit.

As long as I see the burnt area of the board, there are not active components there. They are just wires and a passive diode. I remember those components are used just to pass the currents to the sensing resistors (thick metal pieces) which are located at right lower side of the white connector. I have some confidence to fix those bypassing the currents putting additional wires directly from the connector to those sensing resistors.

Below is just my assumptions but I dare write here.
The burning was caused by a short circuit of the wrong wiring to the outside 2 bulbs each (totally 4). The wires which were supposed to be connected to 5W filaments were grounded at the sockets. This passed too much currents to sensing lines but the fuse was not open because there existed sensing resistors. Those limited the currents but enough to generate heat to burn the jumper wires on the board.

python

iTrader: (4)

if that's the box in the trunk..good luck finding one for a good price...I know they are not cheap unless u get lucky finding one in a junk yard or ebay

steve2006

Several on ebay this one is just $15.00.
I would recheck all your bulbs and wiring before fitting a replacement though looking at the original.


http://www.ebay.com/itm/90-94-LEXUS-LS400-LAMP-FAILURE-SENSOR-LS-400-BRAKE-LIGHT-LAMP-RELAY-89373-50010-/181218311513?pt=Motors_Car_Truck_Parts_Accessories&fits=Make%3ALexus%7CModel%3ALS400&hash=item2a3173fd59&vxp=mtr

python

iTrader: (4)

he may have something causing that box to fail...but it def. needs replacing

geoprz

Okay finally it's fixed!

At first it was the wrong bulbs that blew the black box without me knowing. So still thinking that it was the wrong bulbs I went directly to Toyota to buy the proper ones. I installed the new ones and of course it doesn't matter because the box is blown (still not knowing that was the issue). Finally after doing research I went to check
On the black box and it was blown.

So I bought a used oem one for 50 dollars. Installed it tonight and presto everything is back to normal.

Question though:

With these after market tail lights the section that's attached to the truck has two bulbs. One reverse and one which is suppose to be the part of the braking lights. It made sense with the oem tail lights because there was no white strip. So what do people do with this useless light now, just take it out? Kinda wished I had my oem look back...

geoprz

With these after market tail lights the section that's attached to the truck has two bulbs. One reverse and one which is suppose to be the part of the braking lights. It made sense with the oem tail lights because there was no white strip. So what do people do with this useless light now, just take it out? Kinda wished I had my oem look back...

johnnyg66

I don't know what happened to your setup but mine have all worked perfect since day one. When my harness failed it was before I got these new lights. Don't remember anyone else here with your same issue.