Australian F Sports have them as standard.....look much brighter, camera doesn't pick them up correctly.

 

How do you turn them on? Is there a separate switch or does the turn signal stalk incorporate the switch? Thanks.

 

Probably comes on with the front fogs.
Too amny Audi drivers have them in clear nights, your eyes hurt just stopping behind them at the red lights.

 

included with the indicator/lights switch - thumbwheel turn one notch for front fogs then another turn for rear fogs. Has an orange dash indicator so shows up quite clearly.

 

What would be the point of rear fog lights?

 

High intensity lights cut through the fog/mist so following cars can see you. Very common throughout Europe

 

Rear fog lamps are required on all vehicles sold in Europe per EU regulation 48 and there are regulations governing when they can be used. All vehicles made by Toyota and sold in Europe, including Lexus, have them. Even travel trailers and hitch mounted bike racks have rear fog lamps.

I think it was in 2013 that a new EU requirement was implemented that required rear fog lamps had to be re-activated by the driver if he inadvertently left them on when he turned off the ignition.

Rear fog lamps should be used only when visibility is really horrible such as in very heavy fog, torrential rain, or a white-out blizzard. My rule of thumb is to turn them on only when visibility is so bad that I'm having difficulty or cannot see vehicles driving ahead of me. I've sometimes turned them on for less than a minute at a time during particularly heavy downpours or fog and turned them back off as soon as conditions improved. Maybe it's because rear fog lamps are fairly rare in the U.S. but I've noticed that using them seems to have a moderating effect on drivers who are driving too fast for conditions, i.e. they seem to slow down and stop flying past me driving blind.

I almost always install an E-approved rear fog lamp when I buy a new vehicle that doesn't come with one or two. Attached is a photo of the ones I installed on two of our current vehicles - purchased on eBay Germany.

 

@Kansas share a link to the one you have

 

I'll add that rear fog lamps can also guard against drunk and poor drivers in inclement weather as both tend to follow the driver in front of them. The more distance you can add to these types of drivers seeing you, the better the stopping distance between you and them.

 

The rear fog lamp is the "Klare LED-NSL/Nebelschlussleuchte" from seller "lightsforbikes" on eBay Germany and it has the E4/Netherlands approval symbol. If the following link doesn't work, search for the string in quotes in the previous sentence on eBay Germany: http://www.ebay.de/itm/Klare-LED-NSL...8P6WPzRH9Qp4-g

This unit is primarily targeted for use on non-complying vehicle imported to Europe. I bought it at the recommendation of a German friend who bought one for his U.S. market Toyota Sienna imported to Germany. The lamp module is designed to be surface mounted but I found it easy to fabricate a bracket that allows mounting it below a bumper cover. There are differing opinions on whether one or two rear fog lamps are best - my opinion is that one rear fog lamp is better in that following drivers are less likely to confuse it with tail or brake lamps. Quality is very good - better than any other rear fog lamp I have purchased. Service from lightsforbikes has been excellent.

 

I'm wondering if any of these rear fog lamps can be connected to the existing trailer connection?

 

I don't know how that could work. A North American Lexus RX does not have a rear fog lamp switch and its trailer harness does not have a wire/pin for a rear fog lamp.. A 13-pole European market Lexus RX trailer harness, however, does have a wire/pin for a rear fog lamp and there is a switch for the driver to turn them on and off. All European market trailer harnesses have provision for a rear fog lamp and all European vehicles have a rear fog lamp switch.

There isn't a universal technique for activating inactive existing rear fog lamps on vehicles that have them or for installing aftermarket rear fog lamps. It depends on the situation. Some U.S. market vehicles I've owned (e.g. Mercedes) have had all components for rear fog lamps except for the wiring and the lamp sockets and it was a matter of procuring and installing additional sockets in the existing rear lamp modules and then running wires from them to an existing multi-function dashboard switch. Other vehicles have required starting from scratch - installing a separate rear fog lamp unit, running wires to an aftermarket dashboard switch, sometimes installing a relay in the circuit and usually powering the rear fog lamps from the front fog lamp circuit.

There are numerous wiring diagrams on the Internet that can be found by searching for something like "rear fog light wiring diagram".

 

Common because rear fog light, or lights, are required in Europe by law.