HarrierAWD

Is there a way to retrofit the RX300 so that it can turn on the fog lights only without the headlights on?

I was driving thru thick fog the other day. The HID light bounced back so much that I could barely see the road. I'd like to turn only the fog lights on next time.

Thanks.

cnynctry

I can't take credit for finding this. It was on the internet from another forum. I wish I could remember who and where to give them credit. This information is from a 2001 RX shop manual. If you have a different year it may not work. Maybe the person that posted it will raise their hand and take credit.



At the combination switch located at the foot of the turn signal/lighting stalk, move the (solid green) wire at pin 17 of the combination switch to pin 16 or simply connect it to the ground wire already on pin 16.

At the body ECU, under the dash and up to the left (toward the driver's door)of the stearing column, connect the green wire with the yellow stripe at B6-7 to the brown wire with a white stripe at B8-6. They need not be disconnected from the body ECU.

There are four multi-pin connectors going into the vertically mounted body ECU. Regretably the first wire you need to reach, B8-6, BR-W, is at the very top (center pin of three) of the topmost connector. The second wire, B6-7, G-Y, is in the bottom row of the second connector from the bottom.

This will result in the fog light control relay always being energised if the "stalk" light control is in the fog light on position and the tail light relay is energized. So now the fog lights can be on anytime the parking/tail lights are on and they will extinguish automatically, in the normal fashion, as always.

Both connections are required.
Without the stalk modification the fog light "grnd", negative return circuit will not complete without the low beams being on. And without the ECU mode the grnd signal from the stalk mode cannot pass to the fog light relay.
And as I said, you don't have to remove the wires from the ECU connectors, just add a jumper connection between them.

HarrierAWD

Thanks! That's great information. I'll show it to my dealer to see if they would do it for me. Thanks a lot.

Vlado

I have a 99 rx300 and the mode worked when connecting ( soldering the wires ) mentioned above. Now the fog lights will work alongside all three - marker lights, low beams and high beams!
The procedure requires some basic soldering skills, for the sake of good connections, a Philips screw driver and a 10mm socket.
The driver's side foot well covers have to be removed ( both plastic and metal ) and then the steering column bottom half of the cover. Locating the wires at the body ecu is fairly easy.
On the switch ( indicator stalk ) you have to cut the green wire off of pin17 and connect it to the wire at pin 16.
On the body ecu find the Green/yellow wire and the Brown/white wire and connect them together without cutting then off from their respective connectors at the body ecu.
Now you should have working fog lights as soon as you click to the marker lights position and the fogs would stay illuminated with high beam as well.

the connector at the bottom of the indicator stalk - steering column

The brown/white wire at the body ecu - driver foot well - already soldered to an extension wire...

Body ecu - driver foot well - Green/yellow wire bared and ready for the loop wire to be soldered...

Body ecu - driver foot well - Green/yellow wire bared and ready for the loop wire to be soldered

loop wire soldered connecting the Green/yellow wire to the Brown/white wire...

this is how the foot well/steering column look look wit the covers off...

body ecu visible in the back of the picture - it is held by two 10mm nuts

body ecu bottom nut removed for easier access to the Green/yellow wire...

body ecu - brown/white wire visible at the top...

metal foot well cover that has to be removed as well...

salimshah

Guys just be careful making this mod. For a vehicle to be designated as "street legal" [to be allowed to be driven on the hwy system and city streets] the lighting must meet established standards and the vehicle manufacturers have to submit to elaborate testing. The lighting not only provides light to the driver of the vehicle. it also serves provides visual clues to the other drivers. It can be non-intuitive things like distance from the edge [ex: the fog light source can be 1/2" further away from the edge etc].

So please check the codes.

Salim

Vlado

The codes that a vehicle has to pass to be street legal do not necessarily make it safer.
Mostly, the codes are made by people for people with not much of a common sense.
One should know, out of common sense, that driving with fog light only will make you much less visible for other drivers, just like driving on high beams will blind other drivers, but yet a lot of people don't care, or just lack that common sense and should not have driving priviledges, in my opinion, but that's a whole different story.
In Short,
This Modification, will be very helpful for the few that have to go through fog "thick enough to cut by knife" on regular basis, for others - it will be a waste of time.

salimshah

As a moderator in Club Lexus RX300 forum, I am duty bound to point out when an action being discussed has potential of breaking the law. It is all up to the readers/members obey the law [driving below posted speeds, obeying traffic laws, emission standards etc etc]. I know I am sounding sanctimonious, please bear with me, as the alternative would be to delete the thread.

Disclaimer has been added and it its all up to readers/members to think out the consequences of their actions.

Salim

Vlado

Salim,
If you feel that this discussion steers people into unlawful doing and if you're duty bound by your "job" as a moderator to point out that, please go to the alternative and delete this thread and delete my profile as well.
I'll be more than happy to Not give out know how for free here, but rather charge for it at my shop.
Thank you and good day!

jimbug

Salim makes a good point. I served as a wildlife officer with responsibility for enforcement of boating laws on TN waterways. What we encountered was boaters (mostly fishermen) putting a dimmer switch on their 360 degree rear anchor light to keep it from being so bright while they were fishing. Since it was dimmer it gave the impression to other boaters that the modified fishing boat was further away than it actually was. This lead to accidents (some fatal) and we worked many long nights for years trying to eliminate these type of modifications. Food for thought.

2002RX300

Vlado thanks for the info and the pics!

Salim is just doing his due diligence as a Mod, he's not saying your info isn't appreciated or useful.

I can't even see how these are considered "Fog Lights" but really more just parking lights, still too high to cut under any fog.

Up here in Lake Tahoe NV we have way too many idiots with big trucks who insist on always having their "Fog Lights" on when we actually only get fog about 5 days a year (much like having high beams on).

These big trucks are never low enough to actually cut under any fog.

Cutting under the fog is the whole purpose for "Fog Lights" and can understand the reason for the Thread Starters frustration.

Lexus got smarter with the Gen2 RX330 and separated the "Fog Lights" from the headlights and integrated them lower into the bumper.

HarrierAWD, if you get a lot of fog in your area I would install road legal aftermarket "Fog Lights" in the bumper.